TAFRO Syndrome: Guidance for Managing Patients Presenting Thrombocytopenia, Anasarca, Fever, Reticulin Fibrosis, Renal Insufficiency, and Organomegaly.

TAFRO syndrome is an inflammatory disorder of unknown etiology characterized by thrombocytopenia, anasarca, fever, reticulin fibrosis, renal insufficiency, and organomegaly. Despite great advancements in research on the TAFRO syndrome in the last decade, its diagnosis and treatment are still challenging for most clinicians because of its rarity and severity. Since the initial proposal of the TAFRO syndrome as a distinct disease entity in 2010, two independent diagnostic criteria have been developed. Although these are different in the concept of whether TAFRO syndrome is a subtype of idiopathic multicentric Castleman disease or not, they are similar except for the magnitude of lymph node histopathology. Because there have been no specific biomarkers, numerous diseases must be ruled out before the diagnosis of TAFRO syndrome is made. The standard of care has not been fully established, but interleukin-6 blockade therapy with siltuximab or tocilizumab and anti-inflammatory therapy with high-dose corticosteroids are the most commonly applied for the treatment of TAFRO syndrome. The other immune suppressive agents or combination cytotoxic chemotherapies are considered for patients who do not respond to the initial treatment. Whereas glowing awareness of this disease improves the clinical outcomes of patients with TAFRO syndrome, further worldwide collaborations are warranted.

Immunohistochemical and molecular profiles of heterogeneous components of metaplastic breast cancer: a squamous cell carcinomatous component was distinct from a spindle cell carcinomatous component.

Metaplastic breast carcinoma (MBC), a category of breast cancer, includes different histological types, which are occasionally mixed and heterogeneous. Considering the heterogeneity of cancer cells in a tumour mass has become highly significant, not only from a biological aspect but also for clinical management of recurrence. This study aimed to analyse the immunohistochemical and molecular profiles of each MBC component of a tumour mass. Twenty-five MBC tumours were histologically evaluated, and the most frequent MBC component (c) was squamous cell carcinoma (SCC), followed by spindle cell carcinoma (SpCC). A total of 69 components of MBC and non-MBC in formalin-fixed paraffin-embedded sections were examined for 7 markers by immunohistochemistry. SCC(c) were significantly PTEN negative and CK14 positive, and SpCC(c) were significantly E-cadherin negative and vimentin positive. Multivariate analyses revealed that immunohistochemical profiles of normal/intraductal (IC)(c), no special type (NST)(c), and MBC(c) differed; moreover, SCC(c) and SpCC(c) were distinctly grouped. PTEN gene mutation was detected only in SCC(c) (2/7), but not in SpCC(c). Next-generation sequence analyses for 2 cases with tumours containing SCC(c) demonstrated that PTEN gene mutation increased progressively from IC(c) to NST(c) to SCC(c). In conclusion, the immunohistochemical and molecular profiles of the SCC(c) of MBC are distinct from those of the SpCC(c).

Different effects of crizotinib treatment in two non-small cell lung cancer patients with SDC4::ROS1 fusion variants.

The possibility of stratifying patients according to differences in ROS proto-oncogene 1 (ROS1) fusion partners has been discussed. This study aimed to clarify the clinicopathological differences between two SDC4::ROS1 positive NSCLC cases who had different responses to crizotinib. Cytology and pathology samples from two NSCLC cases with SDC4::ROS1 who were diagnosed and treated with crizotinib at Nihon University Itabashi Hospital were obtained. Case 1 has been well-controlled with crizotinib for over 5 years, but case 2 was worse and overall survival was 19 months. Sequencing analysis of ROS1 fusion genes was performed by reverse-transcription-PCR and Sanger's sequencing methods. In addition, thyroid transcription factor (TTF)-1, ROS-1, Ki67, and phosphorylated extracellular signal-regulated kinase (pERK)1/2 expression were investigated using immunohistochemistry. Sequencing analysis showed SDC4 exon2::ROS1 exon 32 (exon33 deleted) in case 1, and coexistence of SDC4 exon2::ROS1 exon 34 and SDC4 exon2::ROS1 exon35 in case 2. The Ki67 index was not different, but ROS1 and pERK1/2 expression levels tended to be higher in the tumor cells of case 2 than in case 1. Therapeutic response to crizotinib and patients' prognosis in ROS1 rearranged NSCLC may be related to the activation of ROS1 signaling, depending on ROS1 and pERK1/2 overexpression status, even if the ROS1 fusion partner is the same.

The complete mitochondrial genome of water flea Ceriodaphnia dubia (Crustacea: Cladocera) NIES strain.

Water flea Ceriodaphnia dubia has been widely used for risk assessments of chemicals and environmental contamination. In this study, the complete mitochondrial genome (mitogenome) of this species NIES strain was determined using short-read high throughput and long-read sequencing technologies. The mitogenome of C. dubia was 15,170 bp in length and consisted of 13 protein-coding genes (PCGs), 2 ribosomal RNAs (rRNAs), and 22 transfer RNAs (tRNAs). The gene order was identical to the pattern conserved across crustaceans. The complete mitogenome of the NIES strain will serve as genetical reference in ecological risk assessments in Japan, as well as resources for future phylogenetical studies using cladocerans.

Correlations between class I glucose transporter expression patterns and clinical outcomes in non-small cell lung cancer.

BACKGROUND: Glucose transporters (GLUTs) are highly expressed in various cancers. However, the implications of these variable expression patterns are unclear. This study aimed to clarify the correlation between class I GLUT expression patterns and clinical outcomes in non-small cell lung cancer (NSCLC), including their potential role in inflammatory signaling. METHODS: Biopsy tissues from 132 patients with NSCLC (92 adenocarcinomas [ADC] and 40 squamous cell carcinomas [SQCC]) were analyzed. mRNA expression levels of class I GLUTs (solute carrier 2A [SLC2A]1, SLC2A2, SLC2A3, and SLC2A4) and inflammation-related molecules (toll-like receptors TLR4, RelA/p65, and interleukins IL8 and IL6) were measured. Cellular localization of GLUT3 and GLUT4 was investigated using immunofluorescence. RESULTS: Single, combined, and negative GLUT (SLC2A) expression were observed in 27/92 (29.3%), 27/92 (29.3%), and 38/92 (41.3%, p < 0.001) of ADC and 8/40 (20.0%), 29/40 (72.5%, p < 0.001), and 3/40 (7.5%) of SQCC, respectively. In ADC, the single SLC2A3-expressed group had a significantly poorer prognosis, whereas the single SLC2A4-expressed group had a significantly better prognosis. The combined expression groups showed no significant difference. SLC2A expression was not correlated with SQCC prognosis. SLC2A4 expression correlated with lower IL8 expression. GLUT3 and GLUT4 expressions were localized in the tumor cytoplasm. CONCLUSIONS: In lung ADC, single SLC2A3 expression correlated with poor prognosis, whereas single SLC2A4 expression correlated with better prognosis and lower IL8 expression. GLUT3 expression, which is increased by IL8 overexpression, may be suppressed by increasing the expression of GLUT4 through decreased IL8 expression.

Influence of water exchange rates on toxicity and bioaccumulation of hydrophobic organic chemicals in sediment toxicity tests.

In standardized sediment toxicity tests, the applied water exchange methods range from static to flow-through conditions and vary between protocols and laboratories even for the same test species. This variation potentially results in variable chemical exposure, hampering the interpretation of toxicity and bioaccumulation. To address these issues, we performed sediment toxicity tests with a mixture of three polycyclic aromatic hydrocarbons (PAHs) and the freshwater epibenthic amphipod Hyalella azteca as model chemicals and organism, respectively. Five standardized water exchange methods were applied: static, semi-static, or flow-through conditions. By measuring total (Cdiss) and freely dissolved concentrations (Cfree) of PAHs with water sampling and direct immersion solid-phase microextraction methods, respectively, we found that Cdiss in overlying water differed by a factor of up to 107 among water exchange conditions, whereas both Cdiss and Cfree in pore water did not differ by more than a factor of 2.6. Similar survival rates, growth rates, and bioaccumulation of PAHs between water exchange methods suggest that H. azteca was predominantly exposed to pore water rather than overlying water. By applying mechanistic kinetic modeling to simulate spatiotemporal concentration profiles in sediment toxicity tests, we discuss the importance of the water exchange rates and resulting temporal and spatial exposure variability for the extrapolation of laboratory sediment toxicity to field conditions, particularly for chemicals with relatively low hydrophobicity and sediments with low organic carbon content.

Freely dissolved concentration profile and Hyalella azteca toxicity of cationic surfactant C12-benzalkonium in spiked-sediment toxicity test.

The freely dissolved concentrations (Cfree) have been considered a useful metric for exposure of aquatic organisms to organic contaminants. However, Cfree for cationic surfactants has rarely been measured, and its use in sediment toxicity tests has not been evaluated. In this study, Cfree of the cationic surfactant benzyldodecyldimethylammonium (C12-benzalkonium; C12-BAC) in water-only and spiked-sediment toxicity tests with the amphipod Hyalella azteca was analyzed using a passive sampling method. Polyacrylate-coated glass fibers were adopted as the passive sampler. Sorption isotherms of C12-BAC to the polyacrylate fibers were measured in chemical conditions comparable to those of the toxicity tests and used for Cfree calculation in both tests. Detailed concentration analysis in the sediment toxicity test demonstrated a high concentration gradient of C12-BAC between sediment and overlying water; Cfree in pore water was 17-78 times higher than Cfree in overlying water and was 7.2-13 times higher than Cfree at the sediment-water interface. The 50 % lethal concentration and bioconcentration factor of H. azteca obtained in the water-only test (23 µg/L and 140 ± 70 L/kg-wet, respectively) agreed with those calculated based on Cfree in pore water in the sediment test (49 µg/L and 140 ± 90 L/kg-wet, respectively), indicating that H. azteca is exposed mainly to the freely dissolved fraction in pore water. We concluded that Cfree in pore water is a useful exposure metric for H. azteca to cationic surfactants.

Comparing 10- and 28-Day Sediment Toxicity and Bioaccumulation of Fluoranthene in Hyalella azteca Using Passive Sampling Techniques.

Understanding the changes in the temporal and spatial concentrations of chemical substances in sediment toxicity tests facilitates interpretation of their toxicity and accumulation in benthic organisms because benthic organisms are affected by chemicals via multiple exposure pathways. However, such investigations using chronic sediment toxicity tests have rarely been performed. To examine the concentration profiles of a hydrophobic organic chemical using chronic spiked-sediment toxicity tests, we performed 28-day sediment toxicity tests of fluoranthene with a freshwater amphipod, Hyalella azteca, using a semi-flow-through system and compared the results with those of 10-day tests. In these experiments, we measured various types of fluoranthene concentrations over the test periods: total dissolved (Cdiss ) and freely dissolved (Cfree ) concentrations in overlying water and porewater as well as sediment concentrations. We also examined which concentration correlated with the amphipod bioconcentration factor (BCF). We found that both overlying water and porewater Cfree did not differ significantly on days 10 and 28. Sediment concentrations remained almost stable for 28 days, whereas Cdiss in overlying water varied temporally. These results suggest that the 28-day test provides almost constant concentrations of fluoranthene, particularly in porewater, even in a semi-flow-through system. In addition, the comparison of BCF of fluoranthene on day 10 in the present study with that obtained from water-only tests reported in the literature suggested that Cfree in pore water was the most representative indicator of bioaccumulation in H. azteca. Our findings support the possible use of a water-exchange system in chronic spiked-sediment toxicity tests of hydrophobic organic chemicals. However, further studies using sediments and chemicals with different properties are warranted to generalize the findings of the present study. Environ Toxicol Chem 2022;41:2679-2687. © 2022 SETAC.

Severity Classification of Clinical Signs and Defining the Moribund State as an Experimental Endpoint for Acute Toxicity Testing Using Japanese Medaka (Oryzias latipes).

Use of the moribund state as an endpoint for acute toxicity testing in fish is complicated by the lack of consensus about the sublethal signs that define the state or that can predict imminent death. Defining the moribund state in fish requires determination of the association between each observable sublethal sign and transition to imminent death. To establish a criterion for defining the moribund state in Japanese medaka (Oryzias latipes), we determined death/clinical-sign ratios, defined as the proportion of fish with each clinical sign that transitioned to imminent death, for 13 clinical signs observed in individually housed fish exposed to one of two typical toxicants, three pharmaceuticals, two pesticides, and one metal. Also, the time from onset of each clinical sign to transition to imminent death (referred to as the survival time) was determined by continuous monitoring. Three of the observed clinical signs-immobility, lethargy, and immobility at the surface-were found to be indicators of the moribund state, with each of these signs having a death/clinical-sign ratio of 1.0. Evaluation of the survival time after onset of the other 10 signs enabled determination of whether timely euthanasia would be appropriate, thereby providing a means of reducing the suffering of laboratory fish in the period before death. Environ Toxicol Chem 2022;41:1089-1095. © 2022 SETAC.

Potential differences in chitin synthesis ability cause different sensitivities to diflubenzuron among three strains of Daphnia magna.

Ecotoxicity testing of crustaceans using Daphnia magna has been implemented in the chemical management systems of various countries. While the chemical sensitivity of D. magna varies depending on genetically different clonal lineages, the strain used in ecotoxicity tests, including the acute immobilization test (OECD TG202), has not been specified. We hypothesized that comprehensive gene expression profiles could provide useful information on phenotypic differences among strains, including chemical sensitivity. To test this hypothesis, we performed mRNA sequencing on three different strains (NIES, England, and Clone 5) of D. magna under culture conditions. The resulting expression profile of the NIES strain was clearly different compared to the profiles of the other two strains. Gene ontology (GO) enrichment analysis suggested that chitin metabolism was significantly enriched in the NIES strain compared to that in the England strain. Consistent with the GO analysis, evidence of high levels of chitin metabolism in the NIES strain were observed across multiple levels of biological organization, such as expression of chitin synthase genes, chitin content, and chitinase activity, which suggested that the different strains would exhibit different sensitivities to chemicals used to inhibit chitin synthesis. We found that among all strains, the NIES strain was more tolerant to diflubenzuron, a chitin synthesis inhibitor, with a 14-fold difference in the 48 h-EC50 value for the acute immobilization test compared to the England strain. The present study demonstrates that the differences among strains in chitin metabolism may lead to sensitivity difference to diflubenzuron, and serves as a case study of the usefulness of comprehensive gene expression profiles in finding sensitivity differences.

Juvenile hormone synthesis and signaling disruption triggering male offspring induction and population decline in cladocerans (water flea): Review and adverse outcome pathway development.

Juvenile hormone (JH) are a family of multifunctional hormones regulating larval development, molting, metamorphosis, reproduction, and phenotypic plasticity in arthropods. Based on its importance in arthropod life histories, many insect growth regulators (IGRs) mimicking JH have been designed to control harmful insects in agriculture and aquaculture. These JH analogs (JHAs) may also pose hazards to nontarget species by causing unexpected endocrine-disrupting (ED) effects such as molting and metamorphosis defects, larval lethality, and disruption of the sexual identity. This critical review summarizes the current knowledge of the JH-mediated effects in the freshwater cladoceran crustaceans such as Daphnia species on JHA-triggered endocrine disruptive outputs to establish a systematic understanding of JHA effects. Based on the current knowledge, adverse outcome pathways (AOPs) addressing the JHA-mediated ED effects in cladoceran leading to male offspring production and subsequent population decline were developed. The weight of evidence (WoE) of AOPs was assessed according to established guidelines. The review and AOP development aim to present the current scientific understanding of the JH pathway and provide a robust reference for the development of tiered testing strategies and new risk assessment approaches for JHAs in future ecotoxicological research and regulatory processes.

Summary of 17 chemicals evaluated by OECD TG229 using Japanese Medaka, Oryzias latipes in EXTEND 2016.

In June 2016, the Ministry of the Environment of Japan announced a program "EXTEND2016" on the implementation of testing and assessment for endocrine active chemicals, consisting of a two-tiered strategy. The aim of the Tier 1 screening and the Tier 2 testing is to identify the impacts on the endocrine system and to characterize the adverse effects to aquatic animals by endocrine disrupting chemicals detected in the aquatic environment in Japan. For the consistent assessment of the effects on reproduction associated with estrogenic, anti-estrogenic, androgenic, and/or anti-androgenic activities of chemicals throughout Tier 1 screening to Tier 2 testing, a unified test species, Japanese medaka (Oryzias latipes), has been used. For Tier 1 screening, the in vivo Fish Short-Term Reproduction Assay (OECD test guideline No. 229) was conducted for 17 chemicals that were nominated based on the results of environmental monitoring, existing knowledge obtained from a literature survey, and positive results in reporter gene assays using the estrogen receptor of Japanese medaka. In the 17 assays using Japanese medaka, adverse effects on reproduction (i.e., reduction in fecundity and/or fertility) were suggested for 10 chemicals, and a significant increase of hepatic vitellogenin in males, indicating estrogenic (estrogen receptor agonistic) potency, was found for eight chemicals at the concentrations in which no overt toxicity was observed. Based on these results, and the frequency and the concentrations detected in the Japanese environment, estrone, 4-nonylphenol (branched isomers), 4-tert-octylphenol, triphenyl phosphate, and bisphenol A were considered as high priority candidate substances for the Tier 2 testing.

Comparison of Species Sensitivity Distributions for Sediment-Associated Nonionic Organic Chemicals Through Equilibrium Partitioning Theory and Spiked-Sediment Toxicity Tests with Invertebrates.

Equilibrium partitioning (EqP) theory and spiked-sediment toxicity tests are useful methods to develop sediment quality benchmarks. However, neither approach has been directly compared based on species sensitivity distributions (SSDs) to date. In the present study, we compared SSDs for 10 nonionic hydrophobic chemicals (e.g., pyrethroid insecticides, other insecticides, and polycyclic aromatic hydrocarbons) based on 10-14-day spiked-sediment toxicity test data with those based on EqP theory using acute water-only tests. Because the exposure periods were different between the two tests, effective concentrations (i.e., median effective/lethal concentration) were corrected to compare SSDs. Accordingly, we found that hazardous concentrations for 50% and 5% of species (HC50 and HC5, respectively) differed by up to a factor of 100 and 129 between the two approaches, respectively. However, when five or more species were used for SSD estimation, their differences were reduced to a factor of 1.7 and 5.1 for HC50 and HC5, respectively, and the 95% confidence intervals of HC50 values overlapped considerably between the two approaches. These results suggest that when the number of test species is adequate, SSDs based on EqP theory and spiked-sediment tests are comparable in sediment risk assessments. Environ Toxicol Chem 2022;41:462-473. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Dying for change: A roadmap to refine the fish acute toxicity test after 40 years of applying a lethal endpoint.

The fish acute toxicity test (TG203; OECD, 2019) is frequently used and highly embedded in hazard and risk assessment globally. The test estimates the concentration of a chemical that kills 50% of the fish (LC50) over a 96 h exposure and is considered one of the most severe scientific procedures undertaken. Over the years, discussions at the Organisation for Economic Co-operation and Development (OECD) have resulted in changes to the test which reduce the number of fish used, as well as the development of a (potential) replacement test (TG236, OECD, 2013). However, refinement of the mortality endpoint with an earlier (moribundity) endpoint was not considered feasible during the Test Guideline's (TG) last update in 2019. Several stakeholders met at a UK-based workshop to discuss how TG203 can be refined, and identified two key opportunities to reduce fish suffering: (1) application of clinical signs that predict mortality and (2) shortening the test duration. However, several aspects need to be addressed before these refinements can be adopted. TG203 has required recording of major categories of sublethal clinical signs since its conception, with the option to record more detailed signs introduced in the 2019 update. However, in the absence of guidance, differences in identification, recording and reporting of clinical signs between technicians and laboratories is likely to have generated piecemeal data of varying quality. Harmonisation of reporting templates, and training in clinical sign recognition and recording are needed to standardise clinical sign data. This is critical to enable robust data-driven detection of clinical signs that predict mortality. Discussions suggested that the 96 h duration of TG203 cannot stand up to scientific scrutiny. Feedback and data from UK contract research organisations (CROs) conducting the test were that a substantial proportion of mortalities occur in the first 24 h. Refinement of TG203 by shortening the test duration would reduce suffering (and test failure rate) but requires a mechanism to correct new results to previous 96 h LC50 data. The actions needed to implement both refinement opportunities are summarised here within a roadmap. A shift in regulatory assessment, where the 96 h LC50 is a familiar base for decisions, will also be critical.

Spatiotemporal Distribution of Hydrophobic Organic Contaminants in Spiked-Sediment Toxicity Tests: Measuring Total and Freely Dissolved Concentrations in Porewater and Overlying Water.

The sediment-water interface of spiked-sediment toxicity tests is a complex exposure system, where multiple uptake pathways exist for benthic organisms. The freely dissolved concentration (Cfree ) in sediment porewater has been proposed as a relevant exposure metric to hydrophobic organic contaminants (HOCs) in this system. However, Cfree has rarely been measured in spiked-sediment toxicity tests. We first developed a direct immersion solid-phase microextraction method for measuring Cfree in overlying water and porewater in a sediment test using polydimethylsiloxane-coated glass fibers, resulting in sensitive and repeatable in situ measurements of HOCs. Then, we measured Cfree and total dissolved concentrations (Cdiss ) in the sediment test systems with the freshwater amphipod Hyalella azteca and thoroughly evaluated the temporal and spatial profiles of four HOCs (phenanthrene, pyrene, benzo[a]pyrene, and chlorpyrifos). Furthermore, we examined the relationship between the measured concentrations and the lethality of H. azteca. We found that the test system was far from an equilibrium state for all four chemicals tested, where Cdiss in overlying water changed over the test duration and a vertical Cfree gradient existed at the sediment-water interface. In porewater Cdiss was larger than Cfree by a factor of 170 to 220 for benzo[a]pyrene because of the strong binding to dissolved organic carbon. Comparison of the median lethal concentrations of chlorpyrifos in the sediment test and those in water-only tests indicates that Cfree in porewater was the most representative indicator for toxicity of this chemical. The method and findings presented in the present study warrant further research on the chemical transport mechanisms and the actual exposure in sediment tests using different chemicals, sediments, and test species. Environ Toxicol Chem 2021;40:3148-3158. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Toxicity assessment of typical polycyclic aromatic hydrocarbons to Daphnia magna and Hyalella azteca in water-only and sediment-water exposure systems.

While the equilibrium partitioning (EqP) method has been demonstrated to effectively predict the adverse effects of nonionic organic chemicals in sediment on benthic organisms by sediment toxicity tests, only a limited number of studies have been performed both in water-only and whole-sediment toxicity tests using the same species and verified the validity of EqP-based toxicity assessment. To further examine the validity of the EqP method for application in a wide range of hydrophobicity, we conducted sorption/desorption experiments and both water-only and sediment toxicity tests using a popular aquatic crustacean species, Daphnia magna (48 h), and benthic species Hyalella azteca (96 h) for six typical polycyclic aromatic hydrocarbons (PAHs) with three to five rings and an amine derivative: anthracene, phenanthrene, fluoranthene, pyrene, benzo[a]pyrene, dibenzo[a,h]anthracene, and 1-aminopyrene. The linear sorption coefficient was determined and ranged from 2.7 × 102 (phenanthrene) and 1.2 × 104 L/kg (benzo[a]pyrene) highly depending on the hydrophobicity while the aqueous concentrations were stable after 24 h in the desorption test. As result of acute toxicity tests in the water-only exposure system, anthracene and dibenz[a,h]anthracene were found to be nontoxic to both species, while median effect/lethal concentrations (EC50/LC50) were determined as ranging from 0.66 (benzo[a]pyrene) to 330 µg/L (phenanthrene), and from 11 (1-aminopyrene) to 180 µg/L (phenanthrene) for D. magna and H. azteca, respectively. Among these compounds, three PAHs with three, four, and five rings each, and 1-aminopyrene were subjected to sediment-water toxicity tests. In the sediment-water tests, the LC50 of phenanthrene and pyrene was three to six times higher than that of the water-only tests for H. azteca while the EC50 was 1.1 to 2.0 times higher for D. magna. In contrast, the EC50/LC50 of benzo[a]pyrene (BaP) in the sediment-water toxicity test was more than 5 times higher than that in the water-only test for both H. azteca and D. magna. The EC50/LC50 values of 1-aminopyrene were similar in both the sediment-water and the water-only toxicity tests, ranging narrowly from 21 to 28 µg/L and 8.8 to 11 µg/L for D. magna and H. azteca, respectively. The EC50/LC50 based on the body residue (ER50/LR50) was investigated for two of the representative PAHs, pyrene, and BaP. The ER50/LR50 of pyrene in both species was 2.3 and 11 times higher in the water-only toxicity test for D. magna and H. azteca, respectively, while those of BaP in the sediment-water toxicity test were not calculated for the sediment-water toxicity tests, and the highest body concentration in the sediment-water tests was lower than the ER50/LR50 in the water-only toxicity test. Although the experimental results were comparable with the predicted sediment toxicity values based on the EqP method for the selected PAHs in this study, there is a risk of phenanthrene and pyrene being slightly underestimated (1.4-1.9 fold for phenanthrene and 3.7-6.1 fold for pyrene) by the EqP method for H. azteca. These results reaffirm that the bioavailability of poorly water-soluble chemicals is important for sediment toxicity and that the exposure pathway should be further investigated to avoid under- and overestimation via the EqP method.

Detection of feline norovirus using commercial real-time RT-PCR kit for the diagnosis of human norovirus infection.

Feline noroviruses (FNoVs) are potential clinical pathogens in cats. To perform an epidemiological study of FNoV infection, it is necessary to develop a simple and effective method for virus detection. We investigated whether a commercial human NoV quantitative RT-PCR kit for the detection of human NoVs used in medical practice can be applied for FNoV detection. This kit was capable of detecting the FNoV gene regardless of the genogroup (GIV and GVI) in experimental and field samples. Based on the above findings, it is possible to detect FNoVs using human NoV tests. The relationship between FNoV infection and gastroenteritis in cats may be clarified by applying these methods to an epidemiological survey of FNoVs.

Sources of variation in sediment toxicity of hydrophobic organic chemicals: Meta-analysis of 10-14-day spiked-sediment tests with Hyalella azteca and Chironomus dilutus.

Spiked-sediment toxicity tests with benthic organisms are routinely used to assess the potential ecological impact of sediment-associated hydrophobic organic contaminants. Although several sediment tests have been standardized, experimental factors such as spiking methods still vary between laboratories. To identify the experimental factors that affect the bioavailability of contaminants and account for the highest percentage of the variability of toxicity values (i.e., 50% lethal concentration; LC50), we performed a meta-analysis of published 10-14-day spiked-sediment toxicity tests with the standard test species Hyalella azteca and Chironomus dilutus. Analysis of 172 test records revealed that the variability of sediment LC50s for a given combination of chemical and test species was large. The mean coefficient of variation (CV) was 65%, even after organic carbon normalization, and was slightly larger than the CV in water-only tests (49%). Regression analyses revealed that the most important factor contributing to the variability of the sediment LC50s was sediment type (i.e., environmental or formulated sediment) and that use of formulated sediment (i.e., composed of peat, cellulose, or leaves as organic carbon source) tended to cause higher toxicity than use of environmental sediment. This might be caused by the difference in partitioning the coefficient of organic contaminants and the resulting difference in the bioavailability between sediment types. The effects of other factors, including aging periods and spiking methods, were insignificant or specific to certain chemicals. These discoveries facilitate refinement of the methodologies used in sediment toxicity testing and the correct interpretation of test results. Integr Environ Assess Manag 2021;17:1003-1013. © 2021 SETAC.

Summary of reference chemicals evaluated by the fish short-term reproduction assay, OECD TG229, using Japanese Medaka, Oryzias latipes.

Under the Organisation for Economic Co-operation and Development (OECD), the Ministry of the Environment of Japan (MOE) added Japanese medaka (Oryzias latipes) to the test guideline fish short-term reproduction assay (FSTRA) developed by the United States Environmental Protection Agency (US EPA) using fathead minnow (Pimephales promelas). The FSTRA was designed to detect endocrine disrupting effects of chemicals interacting with the hypothalamic-pituitary-gonadal axis (HPG axis) such as agonists or antagonists on the estrogen receptor (Esr) and/or the androgen receptor (AR) and steroidogenesis inhibitors. We conducted the FSTRA with Japanese medaka, in accordance with OECD test guideline number 229 (TG229), for 16 chemicals including four Esr agonists, two Esr antagonists, three AR agonists, two AR antagonists, two steroidogenesis inhibitors, two progesterone receptor agonists, and a negative substance, and evaluated the usability and the validity of the FSTRA (TG229) protocol. In addition, in vitro reporter gene assays (RGAs) using Esr1 and ARß of Japanese medaka were performed for the 16 chemicals, to support the interpretation of the in vivo effects observed in the FSTRA. In the present study, all the test chemicals, except an antiandrogenic chemical and a weak Esr agonist, significantly reduced the reproductive status of the test fish, that is, fecundity or fertility, at concentrations where no overt toxicity was observed. Moreover, vitellogenin (VTG) induction in males and formation of secondary sex characteristics (SSC), papillary processes on the anal fin, in females was sensitive endpoints to Esr and AR agonistic effects, respectively, and might be indicators of the effect concentrations in long-term exposure. Overall, it is suggested that the in vivo FSTRA supported by in vitro RGA data can adequately detect effects on the test fish, O. latipes, and probably identify the mode of action (MOA) of the chemicals tested.

Production of genome-edited Daphnia for heavy metal detection by fluorescence.

Aquatic heavy metal pollution is a growing concern. To facilitate heavy metal monitoring in water, we developed transgenic Daphnia that are highly sensitive to heavy metals and respond to them rapidly. Metallothionein A, which was a metal response gene, and its promoter region was obtained from Daphnia magna. A chimeric gene fusing the promoter region with a green fluorescent protein (GFP) gene was integrated into D. magna using the TALEN technique and transgenic Daphnia named D. magna MetalloG were produced. When D. magna MetalloG was exposed to heavy metal solutions for 1 h, GFP expression was induced only in their midgut and hepatopancreas. The lowest concentrations of heavy metals that activated GFP expression were 1.2 µM Zn2+, 130 nM Cu2+, and 70 nM Cd2+. Heavy metal exposure for 24 h could lower the thresholds even further. D. magna MetalloG facilitates aqueous heavy metal detection and might enhance water quality monitoring.