A novel MRI-based diagnostic model for predicting placenta accreta spectrum

Objective To develop and evaluate a diagnostic model based on MRI signs for predicting placenta accreta spectrum. Materials and Methods A total of 155 pregnant women were included in this study, randomly divided into 104 cases in the training set and 51 cases in the validation set. There were 93 Non-PAS cases, and 62 cases in the PAS group. The training set included 62 Non-PAS cases and 42 PAS cases. Clinical factors and MRI signs were collected for univariate analysis. Then, binary logistic regression analysis was used to develop independent diagnostic models with clinical relevant risk factors or MRI signs, as well as those combining clinical risk factors and MRI signs. The ROC curve analysis was used to evaluate the diagnostic performance of each diagnostic model. Finally, the validation was performed with the validation set. Results In the training set, four clinical factors (gestity, parity, uterine surgery history, placental position) and 11 MRI features (T2-dark bands, placental bulge, T2 hypointense interface loss, myometrial thinning, bladder wall interruption, focal exophytic mass, abnormal placental bed vascularization, placental heterogeneity, asymmetric placental thickening/shape, placental ischemic infarction, abnormal intraplacental vascularity) were considered as risk factors for PAS. The AUC of the clinical diagnostic model, MRI diagnostic model, and clinical + MRI model of PAS were 0.779, 0.854, and 0.874, respectively. In the validation set, the AUC of the clinical diagnostic model, MRI diagnostic model, and clinical + MRI model of PAS were 0.655, 0.728, and 0.735, respectively. Conclusion Diagnosis model based on MRI features in this study can well predict placenta accreta spectrum.

Novel patient-specific helical maxillary distractor: an in vitro feasibility study

At present, stock linear distractors are used for internal maxillary distraction osteogenesis. However, the authors' research group has demonstrated, through an in silico analysis, that linear distraction leads to bone deformities and malocclusion, whereas helical distraction can yield ideal outcomes. A system for designing and manufacturing custom helical distractors has recently been developed, and the feasibility of these appliances now needs to be assessed. This study was, therefore, conducted to gain an initial insight into their feasibility. The study had two goals. First, it aimed to demonstrate, in an in vitro model, that the novel system of custom helical distraction can produce appropriate clinical outcomes. The second aim was to compare the performance of custom helical distractors with that of stock devices and hybrid devices (i.e., linear appliances that feature patient-specific footplates). Interpreting the results as trends, this study showed that the system of custom helical distraction resulted in in vitro outcomes that were superior to those obtained with stock and hybrid devices.

Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15  PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10  TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60  TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

Erratum: Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande [Phys. Rev. Lett. 130, 031802 (2023)]

This corrects the article DOI: 10.1103/PhysRevLett.130.031802.

Measurements of neutrino oscillation parameters from the T2K experiment using 3.6×1021 protons on target

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7 ( 16.3 ) × 10 20 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7 × 10 20 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin 2 θ 13 and the impact of priors on the δ CP measurement. Both analyses prefer the normal mass ordering and upper octant of sin 2 θ 23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin 2 θ 13 from reactors, sin 2 θ 23 = 0 . 561 - 0.032 + 0.021 using Feldman-Cousins corrected intervals, and Δ m 32 2 = 2 . 494 - 0.058 + 0.041 × 10 - 3 eV 2 using constant Δ χ 2 intervals. The CP-violating phase is constrained to δ CP = - 1 . 97 - 0.70 + 0.97 using Feldman-Cousins corrected intervals, and δ CP = 0 , π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2 σ credible level using a flat prior in δ CP , and just below 2 σ using a flat prior in sin δ CP . When the external constraint on sin 2 θ 13 is removed, sin 2 θ 13 = 28 . 0 - 6.5 + 2.8 × 10 - 3 , in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

Prediction of histopathologic grades of myxofibrosarcoma with radiomics based on magnetic resonance imaging

PURPOSE

To develop a radiomics-based model from preoperative magnetic resonance imaging (MRI) for predicting the histopathological grades of myxofibrosarcoma.

METHODS

This retrospective study included 54 patients. The tumors were classified into high-grade and low-grade myxofibrosarcoma. The tumor size, signal intensity heterogeneity, margin, and surrounding tissue were evaluated on MRI. Using the least absolute shrinkage and selection operator (LASSO) algorithms, 1037 radiomics features were obtained from fat-suppressed T2-weighted images (T2WI), and a radiomics signature was established. Using multivariable logistic regression analysis, three models were built to predict the histopathologic grade of myxofibrosarcoma. A radiomics nomogram represents the integrative model. The three models' performance was evaluated using the receiver operating characteristics (ROC) and calibration curves.

RESULTS

The high-grade myxofibrosarcoma had greater depth (P = 0.027), more frequent heterogeneous signal intensity at T2WI (P = 0.015), and tail sign (P = 0.014) than the low-grade tumor. The area under curve (AUC) of these conventional MRI features models was 0.648, 0.656, and 0.668, respectively. Seven radiomic features were selected by LASSO to construct the radiomics signature model, with an AUC of 0.791. The AUC of the integrative model based on radiomics signature and conventional MRI features was 0.875. The integrative model's calibration curve and insignificant Hosmer-Lemeshow test statistic (P = 0.606) revealed good calibration.

CONCLUSION

An integrative model using radiomics signature and three conventional MRI features can preoperatively predict low- or high-grade myxofibrosarcoma.

A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst

Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory of the bright GRB 221009A, which serendipitously occurred within the instrument field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger, then rose to a peak about 10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

Molecular dynamics of interfacial crystallization of dodecane on hydroxylated silica surface impacted by H2O and CO2

The morphology of dodecane in a nanopore at temperatures typical in exploited or depleted oil reservoirs is investigated using molecular dynamics simulation. The dodecane morphology is found to be determined by interactions between interfacial crystallization and surface wetting of the simplified oil, while "evaporation" only plays a minor role. The morphology changes from an isolated, solidified dodecane droplet to a film with orderly lamellae structures remaining within, and finally to a film containing randomly distributed dodecane molecules, as the system temperature increases. In a nanoslit under the impact of water, since water wins against oil in surface wetting on the silica surface due to electrostatic interaction induced hydrogen bonding between water and the silanol group of silica, the spreading of dodecane molecules over the silica surface is impeded by this water confinement mechanism. Meanwhile, interfacial crystallization is enhanced, leading to always an isolated dodecane "droplet," with crystallization weakening as the temperature increases. Since dodecane is immiscible to water, there is no mechanism for dodecane to escape the silica surface, and the competition of surface wetting between water and oil determines the morphology of the crystallized dodecane droplet. For the CO2-dodecane system in a nanoslit, CO2 is an efficient solvent for dodecane at all temperatures. Therefore, interfacial crystallization rapidly disappears. The competition of surface adsorption between CO2 and dodecane is secondary for all cases. The dissolution mechanism is a clear clue for the fact that CO2 is more effective than water flooding in oil recovery for a depleted oil reservoir.

Prognostic value of combined pre- and postoperative albumin-to-alkaline phosphatase ratio for patients with hepatocellular carcinoma undergoing trans-catheter chemoembolisation

AIM

To reveal the prognostic value of the postoperative and dynamic albumin-to-alkaline phosphatase ratio (AAPR) in hepatocellular carcinoma (HCC) patients undergoing trans-catheter chemoembolisation (TACE).

MATERIALS AND METHODS

In total, 545 HCC patients undergoing initial TACE were enrolled into the study. The receiver operating characteristic (ROC) curve was plotted to determine the best cut-off for AAPR. Univariate and multivariate Cox regression analyses were used to confirm the independent prognostic effect of AAPR on overall survival (OS). The predictive performance of AAPR was assessed by ROC curves, concordance index (C-index), and Akaike information criterion (AIC), and was compared to existing liver function assessment systems.

RESULTS

The optimal cut-off value for the AAPR was 0.26. Elevated AAPR (>0.26) was associated with a low risk of death after adjustment whether before (HR: 0.53; 95% CI: 0.4-0.69) or after (HR: 0.64; 95% CI: 0.43-0.95) TACE treatment. The combined pre- and postoperative AAPR showed much better performance in ROC curve (1-, 3-, and 5-year AUCs: 0.69, 0.71, 0.69), C-index (0.65; 95% CI: 0.59-0.72) and AIC analyses than pre-AAPR and post-AAPR alone or liver function assessment systems.

CONCLUSION

This study demonstrated both preoperative and postoperative AAPR were independent prognostic factors for HCC patients undergoing TACE. In addition, the combined pre- and post-AAPR showed better predictive performance than pre-AAPR and post-AAPR alone or liver function assessment systems.

[Allogeneic hematopoietic stem cell transplantation in acute leukemia patients with the SET-NUP214 fusion gene: Efficacy and survival analysis]

Objective: To investigate the clinical efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with acute leukemia who are positive for the SET-NUP214 fusion gene (SET-NUP214⁺AL). Methods: This was a retrospective case series study. Clinical data of 18 patients with SET-NUP214⁺AL who received allo-HSCT in the First Affiliated Hospital of Soochow University and Soochow Hongci Hematology Hospital from December 2014 to October 2021 were retrospectively analyzed to investigate treatment efficacy and prognosis. The Kaplan-Meier method was used for survival analysis. Results: Of the 18 patients, 12 were male and 6 were female, and the median age was 29 years (range, 13-55 years). There were six cases of mixed phenotype acute leukemia (three cases of myeloid/T, two cases of B/T, one case of myeloid/B/T), nine cases of acute lymphoblastic leukemia (ALL) (one case of B-ALL and eight cases of T-ALL), and three cases of acute myeloid leukemia. All patients received induction chemotherapy after diagnosis, and 17 patients achieved complete remission (CR) after chemotherapy. All patients subsequently received allo-HSCT. Pre-transplantation status: 15 patients were in the first CR, 1 patient was in the second CR, 1 was in partial remission, and 1 patient did not reach CR. All patients were successfully implanted with stem cells. The median time of granulocyte and platelet reconstitution was +12 and +13 days, respectively. With a median follow-up of 23 (4-80) months, 15 patients survived, while 3 patients died. The cause of death was recurrence of SET-NUP214⁺AL after transplantation. After allo-HSCT, 5 patients relapsed. The estimated 3-year overall survival (OS) and relapse-free survival (RFS) rates were 83.3%±15.2% and 55.4%±20.7%, respectively. Among the 15 patients who achieved CR before transplantation, there was no significant difference in OS and RFS between haploidentical HSCT and matched sibling donor HSCT (all P>0.05). Conclusions: Allo-HSCT can improve the prognosis and long-term survival rate of patients with SET-NUP214⁺AL. Disease recurrence is the most important factor affecting long-term survival.

Sequence-to-Sequence Change-Point Detection in Single-Particle Trajectories via Recurrent Neural Network for Measuring Self-Diffusion

A recurrent neural network is developed for segmenting between anomalous and normal diffusion in single-particle trajectories. Accurate segmentation infers a distinct change point that is used to approximate an Einstein linear regime in the mean-squared displacement curve via the transition density function, a unique physical descriptor for short-lived and delayed transiency. Through several artificial and simulated scenarios, we demonstrate the compelling accuracy of our model for dissecting linear and nonlinear behaviour. The inherent practicality of our model lies in its ability to substantiate the self-diffusion coefficient through offline trajectory segmentation, which is opposed to the common ‘best-guess’ linear fitting standard. Additionally, we show that the transition density function has fundamental implications and correspondence to underlying mechanisms that influence transition. In particular, we show that the known proportionality between salt concentration and diffusion of water also influences delayed anomalous behaviour.

Cold stress triggers freezing tolerance in wheat (Triticum aestivum L.) via hormone regulation and transcription of related genes

Low temperatures limit the geographic distribution and yield of plants. Hormones play an important role in coordinating the growth and development of plants and their tolerance to low temperatures. However, the mechanisms by which hormones affect plant resistance to extreme cold stress in the natural environment are still unclear. In this study, two winter wheat varieties with different cold resistances, Dn1 and J22, were used to conduct targeted plant hormone metabolome analysis on the tillering nodes of winter wheat at 5 °C, -10 °C and -25 °C using an LC-ESI-MS/MS system. We screened 39 hormones from 88 plant hormone metabolites and constructed a partial regulatory network of auxin, jasmonic acid and cytokinin. GO analysis and enrichment of KEGG pathways in different metabolites showed that the 'plant hormone signal transduction' pathway was the most common. Our study showed that extreme low temperature increased the most levels of auxin, cytokinin and salicylic acid, and decreased levels of jasmonic acid and abscisic acid, and that levels of auxin, jasmonic acid and cytokinin in Dn1 were higher than those in J22. These changes in hormone levels were associated with changes in gene expression in synthesis, catabolism, transport and signal transduction pathways. These results differ from the previous hormone regulation mechanisms, which were mostly obtained at 4 °C. Our results provide a basis for further understanding the molecular mechanisms by which plant endogenous hormones regulate plant freezing stress tolerance.

Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande

We report a search for cosmic-ray boosted dark matter with protons using the 0.37  megaton×years data collected at Super-Kamiokande experiment during the 1996-2018 period (SKI-IV phase). We searched for an excess of proton recoils above the atmospheric neutrino background from the vicinity of the Galactic Center. No such excess is observed, and limits are calculated for two reference models of dark matter with either a constant interaction cross section or through a scalar mediator. This is the first experimental search for boosted dark matter with hadrons using directional information. The results present the most stringent limits on cosmic-ray boosted dark matter and exclude the dark matter-nucleon elastic scattering cross section between 10^{-33}cm^{2} and 10^{-27}cm^{2} for dark matter mass from 1  MeV/c^{2} to 300  MeV/c^{2}.

A Deep-Learning Error Detection System in Radiation Therapy

Delivering radiation therapy based on erroneous or corrupted treatment plan data has previously and unfortunately resulted in severe, sometimes grave patient harm. Aiming to prevent such harm and improve safety in radiation therapy treatment, this work introduces a novel, yet intuitive algorithm for strategically structuring the complex and unstructured data typical of modern treatment plans so their treatment sites may automatically be verified with deep-learning architectures. The proposed algorithm utilizes geometric and dose plan parameters to represent each plan's data as a heat map to feed a deep-learning classifier that will predict the plan's treatment site. Once it is returned by the classifier, a plan's predicted site can be compared to its documented intended site, and a warning raised should the two differ. Using real head-neck, breast, and prostate treatment plan data retrieved at two hospitals in the United States, the algorithm is evaluated by observing the accuracy of convolutional neural networks (ConvNets) in correctly classifying the structured heat map data. Many well-known ConvNet architectures are tested, and ResNet-18 performs the best with a testing accuracy of 97.8% and 0.979 F-1 score. Clearly, the heat maps generated by the proposed algorithm, despite using only a few of the many available plan parameters, retain enough information for correct treatment site classification. The simple construction and ease of interpretation make the heat maps an attractive choice for classification and error detection.

Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9}  GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

Antimony release and volatilization from rice paddy soils: Field and microcosm study

The fate of antimony (Sb) in submerged soils and the impact of common agricultural practices (e.g., manuring) on Sb release and volatilization is understudied. We investigated porewater Sb release and volatilization in the field and laboratory for three rice paddy soils. In the field study, the porewater Sb concentration (up to 107.1 μg L^-1) was associated with iron (Fe) at two sites, and with pH, Fe, manganese (Mn), and sulfate (SO₄^2-) at one site. The surface water Sb concentrations (up to 495.3 ± 113.7 μg L^-1) were up to 99 times higher than the regulatory values indicating a potential risk to aquaculture and rice agriculture. For the first time, volatile Sb was detected in rice paddy fields using a validated quantitative method (18.1 ± 5.2 to 217.9 ± 160.7 mg ha^-1 y^-1). We also investigated the influence of two common rice agriculture practices (flooding and manuring) on Sb release and volatilization in a 56-day microcosm experiment using the same soils from the field campaign. Flooding induced an immediate, but temporary, Sb release into the porewater that declined with SO₄^2-, indicating that SO₄^2- reduction may reduce porewater Sb concentrations. A secondary Sb release, corresponding to Fe reduction in the porewater, was observed in some of the microcosms. Our results suggest flooding-induced Sb release into rice paddy porewaters is temporary but relevant. Manuring the soils did not impact the porewater Sb concentration but did enhance Sb volatilization. Volatile Sb (159.6 ± 108.4 to 2237.5 ± 679.7 ng kg^-1 y^-1) was detected in most of the treatments and was correlated with the surface water Sb concentration. Our study indicates that Sb volatilization could be occurring at the soil-water interface or directly in the surface water and highlights that future works should investigate this potentially relevant mechanism.

[Characteristics analysis of oral clinical trials registered in Chinese Clinical Trial Registry]

Objective: To investigate the project characteristics of oral clinical trials registered in Chinese Clinical Trial Registry (ChiCTR), and to provide reference for medical institutions to improve the quality of oral clinical trials and formulate management systems. Methods: The ChiCTR database was retrieved to collect all the oral-related clinical trials from the time of database establishment to July 25, 2021. Those clinical trials were analyzed statistically in respect of name of registered project, registration time, registration status, regional distribution of research institutions, approval status by ethics committee, sample size, source of funds, involved disease, research type and design, randomization method, and whether blind method was adopted. Results: A total of 778 oral clinical trials, which studied mainly in the oral and maxillofacial diseases, periodontal tissue diseases, oral implant diseases, oral mucosal diseases, and oral prosthetic diseases, were retrieved in the database. Beijing, Sichuan, Shanghai, Guangdong and Hubei were major regions where oral clinical trials were carried out, accounting for 69.68% (772/1 108) of the total. The top four funding sources were hospital finance [24.93% (186/746)], local government finance [22.39% (167/746)], self-financing [17.69% (132/746)], and national finance [12.47% (93/746)]. For the types of researches, 520 interventional studies and 244 observational studies were identified (accounting for 66.84% and 31.36%, respectively). The research designs were dominated by ways of randomized control (381, 48.97%), of which 240 (62.99%) trials were with missing or unspecified blinding methods. Conclusions: Oral clinical trials are increasing year by year, but they are regionally imbalanced, and still need to be further improved in registration information and research design. Administrative departments should pay more attention to strengthen the publicity and education on the registration and publication mechanism of clinical trials, and enhance researchers' cognitions in clinical trials registration and clinical trials design.

Radiological features of Rosai-Dorfman disease: case series and review of the literature

AIM

To improve the accuracy of diagnosis of Rosai-Dorfman disease (RDD) by summarising the computed tomography (CT) and magnetic resonance imaging (MRI) characteristics.

MATERIALS AND METHODS

The clinical manifestations, imaging findings, and pathological characteristics of 14 patients with histopathologically confirmed RDD were analysed retrospectively and a literature review was undertaken.

RESULTS

Of the 14 patients, nine had multiple lesions and five had single lesions. Eight patients had extranodal lesions, while six had mixed-type lesions. In patients with head and neck lesions, plain CT/MRI revealed irregularly shaped, well-defined, homogeneous, and mainly progressive lesions, with marked homogeneous enhancement on multiphasic contrast-enhanced imaging. One patient had dural lesions, one of which iso-intense to grey matter, with patchy hypo-intensity on T2-weighted imaging, meningeal tail signs, and characteristic crabfoot-like enhancement. Three patients with skeletal system involvement exhibited osteolytic bone destruction without sclerosis at the edges, associated soft-tissue masses, or periosteal reactions. Two patients had well-defined subcutaneous lesions, inhomogeneous density, and progressive parenchymal enhancement on contrast-enhanced CT. One patient had multiple intestinal lesions with inhomogeneous nodular thickening of the blind ascending colon and ileum, with marked and progressive enhancement.

CONCLUSION

RDD involvement is mainly multifocal, primarily in the head and neck regions. Plain CT/MRI revealed well-defined, irregularly shaped lesions with homogeneous density/signal, with marked and progressive enhancement on multiphasic contrast-enhanced imaging; however, histopathology is still required to confirm the diagnosis of RDD.

Exposure to Contaminated River Water is Associated with Early Hatching and Dysregulation of Gene Expression in Early Life Stages of the Endangered Copper Redhorse (Moxostoma hubbsi)

The copper redhorse (Moxostoma hubbsi) is an endangered fish that spawns exclusively in the Richelieu River (Quebec, Canada). Tributaries of the Richelieu are contaminated with high levels of current-use pesticides, which may impact early-life stage (ELS) copper redhorse and other native fishes. We assessed the effects of exposure to contaminated river water on ELS copper redhorse and river redhorse (Moxostoma carinatum), a related fish that shares the copper redhorse's spawning grounds and nursery habitat. A riverside flow-through system was used to expose copper and river redhorse embryos (1000 each) to Richelieu River water or laboratory water as a control. Fish were maintained until 14 days posthatch, and water samples were taken daily for chemical analysis. Following a heavy rain event, concentrations of two neonicotinoid pesticides, clothianidin and thiamethoxam, exceeded water quality guidelines for aquatic life (20 ng/L). Using nontargeted screening, we tentatively identified an additional 24 pharmaceutical and personal care products and 23 pesticides in river water. Effects of river water on ELS fish were observed in both species, but the copper redhorse appeared to be more sensitive. Fish exposed to river water hatched 10.7 (copper redhorse) and 2.4 (river redhorse) cumulative degree days earlier than controls. Copper redhorse survival was significantly lower in river water (73 ± 16%) compared to laboratory water (93 ± 3%), whereas river redhorse survival was similar between treatments (84 ± 6% and 89 ± 4%, respectively). Sequencing of copper redhorse larvae RNA revealed 18 differentially expressed genes (DEGs) following 14 days of exposure to river water. Eight up-regulated DEGs were linked to immune function and injury response, and seven down-regulated DEGs were involved with digestion and nutrient absorption. The present study provided valuable data on the effects of ELS exposure to a real-world mixture of contaminants in two fish species of concern. Environ Toxicol Chem 2022;41:1950-1966. © 2022 SETAC.