Enhancing Gene Co-Expression Network Inference for the Malaria Parasite Plasmodium falciparum.

BACKGROUND: Malaria results in more than 550,000 deaths each year due to drug resistance in the most lethal Plasmodium (P.) species P. falciparum. A full P. falciparum genome was published in 2002, yet 44.6% of its genes have unknown functions. Improving the functional annotation of genes is important for identifying drug targets and understanding the evolution of drug resistance. RESULTS: Genes function by interacting with one another. So, analyzing gene co-expression networks can enhance functional annotations and prioritize genes for wet lab validation. Earlier efforts to build gene co-expression networks in P. falciparum have been limited to a single network inference method or gaining biological understanding for only a single gene and its interacting partners. Here, we explore multiple inference methods and aim to systematically predict functional annotations for all P. falciparum genes. We evaluate each inferred network based on how well it predicts existing gene-Gene Ontology (GO) term annotations using network clustering and leave-one-out crossvalidation. We assess overlaps of the different networks' edges (gene co-expression relationships), as well as predicted functional knowledge. The networks' edges are overall complementary: 47-85% of all edges are unique to each network. In terms of the accuracy of predicting gene functional annotations, all networks yielded relatively high precision (as high as 87% for the network inferred using mutual information), but the highest recall reached was below 15%. All networks having low recall means that none of them capture a large amount of all existing gene-GO term annotations. In fact, their annotation predictions are highly complementary, with the largest pairwise overlap of only 27%. We provide ranked lists of inferred gene-gene interactions and predicted gene-GO term annotations for future use and wet lab validation by the malaria community. CONCLUSIONS: The different networks seem to capture different aspects of the P. falciparum biology in terms of both inferred interactions and predicted gene functional annotations. Thus, relying on a single network inference method should be avoided when possible. SUPPLEMENTARY DATA: Attached.

A Plasmodium falciparum genetic cross reveals the contributions of pfcrt and plasmepsin II/III to piperaquine drug resistance.

Piperaquine (PPQ) is widely used in combination with dihydroartemisinin as a first-line treatment against malaria. Multiple genetic drivers of PPQ resistance have been reported, including mutations in the Plasmodium falciparum chloroquine resistance transporter (pfcrt) and increased copies of plasmepsin II/III (pm2/3). We generated a cross between a Cambodia-derived multidrug-resistant KEL1/PLA1 lineage isolate (KH004) and a drug-susceptible Malawian parasite (Mal31). Mal31 harbors a wild-type (3D7-like) pfcrt allele and a single copy of pm2/3, while KH004 has a chloroquine-resistant (Dd2-like) pfcrt allele with an additional G367C substitution and multiple copies of pm2/3. We recovered 104 unique recombinant parasites and examined a targeted set of progeny representing all possible combinations of variants at pfcrt and pm2/3. We performed a detailed analysis of competitive fitness and a range of PPQ susceptibility phenotypes with these progenies, including PPQ survival assay, area under the dose response curve, and a limited point IC50. We find that inheritance of the KH004 pfcrt allele is required for reduced PPQ sensitivity, whereas copy number variation in pm2/3 further decreases susceptibility but does not confer resistance in the absence of additional mutations in pfcrt. A deep investigation of genotype-phenotype relationships demonstrates that progeny clones from experimental crosses can be used to understand the relative contributions of pfcrt, pm2/3, and parasite genetic background to a range of PPQ-related traits. Additionally, we find that the resistance phenotype associated with parasites inheriting the G367C substitution in pfcrt is consistent with previously validated PPQ resistance mutations in this transporter.IMPORTANCEResistance to piperaquine, used in combination with dihydroartemisinin, has emerged in Cambodia and threatens to spread to other malaria-endemic regions. Understanding the causal mutations of drug resistance and their impact on parasite fitness is critical for surveillance and intervention and can also reveal new avenues to limiting the evolution and spread of drug resistance. An experimental genetic cross is a powerful tool for pinpointing the genetic determinants of key drug resistance and fitness phenotypes and has the distinct advantage of quantifying the effects of naturally evolved genetic variation. Our study was strengthened since the full range of copies of KH004 pm2/3 was inherited among the progeny clones, allowing us to directly test the role of the pm2/3 copy number on resistance-related phenotypes in the context of a unique pfcrt allele. Our multigene model suggests an important role for both loci in the evolution of this multidrug-resistant parasite lineage.

Local spatiotemporal dynamics of particulate matter and oak pollen measured by machine learning aided optical particle counters.

Conventional techniques for monitoring pollen currently have significant limitations in terms of labour, cost and the spatiotemporal resolution that can be achieved. Pollen monitoring networks across the world are generally sparse and are not able to fully represent the detailed characteristics of airborne pollen. There are few studies that observe concentrations on a local scale, and even fewer that do so in ecologically rich rural areas and close to emitting sources. Better understanding of these would be relevant to occupational risk assessments for public health, as well as ecology, biodiversity, and climate. We present a study using low-cost optical particle counters (OPCs) and the application of machine learning models to monitor particulate matter and pollen within a mature oak forest in the UK. We characterise the observed oak pollen concentrations, first during an OPC colocation period (6 days) for calibration purposes, then for a period (36 days) when the OPCs were distributed on an observational tower at different heights through the canopy. We assess the efficacy and usefulness of this method and discuss directions for future development, including the requirements for training data. The results show promise, with the derived pollen concentrations following the expected diurnal trends and interactions with meteorological variables. Quercus pollen concentrations appeared greatest when measured at the canopy height of the forest (20-30 m). Quercus pollen concentrations were lowest at the greatest measurement height that is above the canopy (40 m), which is congruent with previous studies of background pollen in urban environments. The attenuation of pollen concentrations as sources are depleted is also observed across the season and at different heights, with some evidence that the pollen concentrations persist later at the lowest level beneath the canopy (10 m) where catkins mature latest in the season compared to higher catkins.

The James A. Rand Young Investigator's Award: Keeping It Simple: Are all Musculoskeletal Infection Society Tests Useful to Diagnose Periprosthetic Joint Infection?

BACKGROUND: Current data evaluating the clinical value and cost-effectiveness of advanced diagnostic tests for periprosthetic joint infection (PJI) diagnosis, including alpha-defensin and synovial C-reactive protein (CRP), is conflicting. This study aimed to evaluate the adequacy of preoperative and intraoperative PJI workups without utilizing these tests. METHODS: This retrospective analysis identified all patients who underwent revision total knee or hip arthroplasty (rTKA and rTHA, respectively) for suspected PJI between 2018 and 2020 and had a minimum follow-up of 2 years. Perioperative data and lab results were collected, and cases were dichotomized based on whether they met the 2018 Musculoskeletal Infection Society (MSIS) criteria for PJI. In total, 204 rTKA and 158 rTHA cases suspected of PJI were reviewed. RESULTS: Nearly 100% of the cases were categorized as "infected" for meeting the 2018 MSIS criteria without utilization of alpha-defensin or synovial CRP (rTKA: n = 193, 94.6%; rTHA: n = 156, 98.7%). Most cases were classified as PJI preoperatively by meeting either the major MSIS or the combinational minor MSIS criteria of traditional lab tests (rTKA: n = 177, 86.8%; rTHA: n = 143, 90.5%). A subset of cases was classified as PJI by meeting combinational preoperative and intraoperative MSIS criteria (rTKA: 16, 7.8%; rTHA: 13, 8.2%). Only 3.6% of all cases were considered "inconclusive" using preoperative and intraoperative data. CONCLUSIONS: Given the high rate of cases satisfying PJI criteria during preoperative workup using our available tests, the synovial alpha-defensin and synovial CRP tests may not be necessary in the routine diagnostic workup of PJI. We suggest that the primary PJI workup process should be based on a stepwise algorithmic approach with the most economical testing necessary to determine a diagnosis first. The use of advanced, commercialized, and costly biomarkers should be utilized only when traditional testing is indeterminate.

Usability of the 4Ms Worksheet in the Emergency Department for Older Patients: A Qualitative Study.

Introduction: Older adults often have multiple comorbidities; therefore, they are at high risk for adverse events after discharge. The 4Ms framework-what matters, medications, mentation, mobility-has been used in acute and ambulatory care settings to identify risk factors for adverse events in older adults, although it has not been used in the emergency department (ED). We aimed to determine whether 1) use of the 4Ms worksheet would help emergency clinicians understand older adult patients' goals of care and 2) use of the worksheet was feasible in the ED. Methods: We conducted a qualitative, descriptive study among patients aged ≥60 years and emergency clinicians from January-June 2022. Patients were asked to fill out a 4Ms worksheet; following this, semi-structured interviews were conducted with patients and clinicians separately. We analysed data to create codes, which were divided into categories and sub-categories. Results: A total of 20 older patients and 19 emergency clinicians were interviewed. We identified two categories based on our aims: understanding patient goals of care (sub-categories: clinician/ patient concordance; understanding underlying goals of care; underlying goals of care discrepancy) and use of 4Ms Worksheet (sub-categories: worksheet to discussion discrepancy; challenges using worksheet; challenge completing worksheet before discharge). Rates of concordance between patient and clinician on main concern/goal of care and underlying goals of care were 82.4% and 15.4%, respectively. Conclusion: We found that most patients and emergency clinicians agreed on the main goal of care, although clinicians often failed to elicit patients' underlying goal(s) of care. Additionally, many patients preferred to have the interviewer fill out the worksheet for them. There was often discrepancy between what was written and what was discussed with the interviewer. More research is needed to determine the best way to integrate the 4Ms framework within emergency care.

Early Initiation of Ceftaroline-Based Combination Therapy for Methicillin-resistant Staphylococcus aureus Bacteremia.

Purpose: Monotherapy with vancomycin or daptomycin remains guideline-based care for methicillin-resistant Staphylococcus aureus bacteremia (MRSA-B) despite concerns regarding efficacy. Limited data support potential benefit of combination therapy with ceftaroline as initial therapy. We present an assessment of outcomes of patients initiated on early combination therapy for MRSA-B. Methods: This was a single-center, retrospective study of adult patients admitted with MRSA-B between July 1, 2017 and April 31, 2023. During this period, there was a change in institutional practice from routine administration of monotherapy to initial combination therapy for most patients with MRSA-B. Combination therapy included vancomycin or daptomycin plus ceftaroline within 72 hours of index blood culture and monotherapy was vancomycin or daptomycin alone. The primary outcome was a composite of persistent bacteremia, 30-day all-cause mortality, and 30-day bacteremia recurrence. Time to microbiological cure and safety outcomes were assessed. All outcomes were assessed using propensity score-weighted logistic regression. Results: Of 213 patients included, 118 received monotherapy (115 vancomycin, 3 daptomycin) and 95 received combination therapy with ceftaroline (76 vancomycin, 19 daptomycin). The mean time from MRSA-positive molecular diagnostic blood culture result to combination therapy was 12.1 hours. There was no difference between groups for the primary composite outcome (OR 1.58, 95% CI 0.60, 4.18). Time to microbiological cure was longer with combination therapy (mean difference 1.50 days, 95% CI 0.60, 2.41). Adverse event rates were similar in both groups. Conclusions: Early initiation of ceftaroline-based combination therapy did not improve outcomes for patients with MRSA-B in comparison to monotherapy therapy.

Membrane-Cloaked Nanoparticles for RNA Interference of ß-Catenin in Triple-Negative Breast Cancer.

There is an outstanding need for targeted therapies for triple-negative breast cancer (TNBC), an aggressive breast cancer subtype. Since TNBC's rapid growth and metastasis are driven by hyperactive Wnt signaling, suppressing the key-pathway mediator ß-catenin through RNA interference may improve patient outcomes. However, small interfering ribonucleic acid (siRNA) molecules require a carrier to elicit targeted gene silencing. Here, we show that 4T1 cancer cell membrane wrapped poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) can deliver siRNA into TNBC cells, silence ß-catenin expression, and reduce the cells' tumorigenic qualities. Compared to unwrapped and nontargeted NPs, the cancer cell membrane wrapped nanoparticles (CCNPs) exhibit dramatically improved uptake by TNBC cells versus breast epithelial cells and greater gene silencing at mRNA and protein levels. Congruently, ß-catenin siRNA-loaded CCNPs significantly activate senescence in 2D cultured TNBC cells and reduce proliferation in 3D spheroids. This work advances the development of nucleic acid carriers for targeted RNA interference therapy.

Social and circadian rhythm dysregulation and suicide: A systematic review and meta-analysis.

This systematic review of 52 studies provides a quantitative synthesis of the empirical literature on social and circadian rhythm correlates of suicidal thoughts and behaviors (STB). Small-to-medium pooled effect sizes were observed for associations between evening chronotype and STB and suicidal ideation (SI), although the pooled effect size diminished when accounting for publication bias. Three studies employed longitudinal designs and suggested eveningness was predictive of future STB, with a small-to-medium effect size. Social rhythm irregularity was also a significant correlate of STB with pooled effect sizes in the medium range. Overall circadian rhythm disruption was not associated with STB, although certain circadian rhythm metrics, including mean daytime activity, circadian rhythm sleep-wake disorder diagnosis, and actigraphy-assessed amplitude were associated with STB. Pooled effect sizes for these indices were in the medium to large range. There is a need for additional longitudinal research on actigraphy-based circadian parameters and objective markers of circadian phase (i.e., dim-light melatonin onset) to gain a clearer understanding of associations of endogenous circadian function and STB beyond that which can be captured via self-report.

Examining the Influence of Imbalanced Social Contact Matrices in Epidemic Models.

Transmissible infections such as those caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread according to who contacts whom. Therefore, many epidemic models incorporate contact patterns through contact matrices. Contact matrices can be generated from social contact survey data. However, the resulting matrices are often imbalanced, such that the total number of contacts reported by group A with group B do not match those reported by group B with group A. We examined the theoretical influence of imbalanced contact matrices on the estimated basic reproduction number (R0). We then explored how imbalanced matrices may bias model-based epidemic projections using an illustrative simulation model of SARS-CoV-2 with 2 age groups (<15 and ≥15 years). Models with imbalanced matrices underestimated the initial spread of SARS-CoV-2, had later time to peak incidence, and had smaller peak incidence. Imbalanced matrices also influenced cumulative infections observed per age group, as well as the estimated impact of an age-specific vaccination strategy. Stratified transmission models that do not consider contact balancing may generate biased projections of epidemic trajectory and the impact of targeted public health interventions. Therefore, modeling studies should implement and report methods used to balance contact matrices for stratified transmission models.

A One Health perspective: COVID-sniffing dogs can be effective and efficient as public health guardians.

Scent-detection dogs have been used for decades to locate drugs, explosives, toxic waste, and more. Scent dogs have been trained to alert for seizures and hypoglycemia, locate cadavers, and screen for viruses, bacterial infections, and numerous cancers. These capable dogs warrant a more significant role in public health protection. The purpose of this preliminary study was to determine whether dogs could be trained to accurately identify coronavirus disease 2019 (COVID-19) infections in humans. In previously published studies, dogs were trained to identify the scent of COVID-19 in inert samples with high sensitivity and specificity. In this study, 2 dogs were trained to identify the scent in live individuals (vs inert samples, as used in previous studies), a faster and more efficient screening method. These dogs tested out at 94% to 96% positive and negative agreement compared to PCR testing. These results recommend the use of scent dogs for public health applications and warrant investigation for other applications beyond COVID-19. This study is included as part of the Currents in One Health series. A partner article by Pellin et al, AJVR, January 2024, describes and evaluates the current research on the utilization of trained scent-detection dogs for the detection of disease within human and veterinary patients.

Indications, Clinical Outcomes, and Re-Revisions Following Revision Total Hip Arthroplasty - Does Age Matter?

BACKGROUND: Younger age is associated with increased revision incidence following primary total hip arthroplasty, though the association between age and repeat revision following revision total hip arthroplasty (rTHA) has not been described. This study aimed to describe the incidences and indications for subsequent revision (re-revision) following rTHA based on age. METHODS: Patients undergoing aseptic rTHA from 2011 to 2021 with minimum 1-year follow-up were retrospectively reviewed. Patients were stratified into 3 groups based on age at the time of index rTHA (ie, <55 years, 55 to 74 years, and >74 years). Perioperative characteristics, complications, and re-revisions were compared between groups. RESULTS: Of 694 included rTHAs, those in the >74 age group were more likely to undergo rTHA for periprosthetic fracture (P < .001) while those in the <55 age group were more likely to undergo rTHA for metallosis/taper corrosion (P = .028). Readmissions (P = .759) and emergency department visits (P = .498) within 90 days were comparable across ages. Rates of re-revision were comparable at 90 days (P = .495), 1 year (P = .443), and 2 years (P = .204). Kaplan-Meier analysis of all-cause re-revision at latest follow-up showed a nonstatistically significant trend toward increasing re-revisions in the <55 and 55 to 74 age groups. Using logistic regressions, smoking and index rTHA for instability were independently associated with re-revision, while age at index surgery was not. CONCLUSIONS: While indications for rTHA differ across age groups, rates of 2-year re-revision are statistically comparable between groups. Further studies are warranted to understand the association between age, activity, and re-revision rates after 5 years postoperatively.

The use of sniffer dogs for early detection of cancer: a One Health approach.

This review, which is part of the "Currents in One Health" series, describes and evaluates the current research on the utilization of trained medical scent detection, aka "sniffer" dogs for the detection of diseases, with particular emphasis on neoplasia, both within human and veterinary patients. A recent study by the authors that used sniffer dogs to detect differences in saliva from dogs diagnosed with various neoplastic processes compared with healthy control dogs is described. The concept of One Health is explored by the description of previous studies that have utilized sniffer dogs in the detection of human neoplasia (focusing on lung, prostate, and breast cancer) and veterinary neoplasia and demonstrating that further research in this arena can benefit multiple species. Future avenues of research and utilization of these findings are outlined. The companion Currents in One Health by Ungar et al, JAVMA, January 2024, addresses the use of sniffer dogs to detect human COVID-19 infections.

Cyclooxygenase inhibition does not blunt thermal hyperemia in skeletal muscle of humans.

Acute heat exposure increases skeletal muscle blood flow in humans. However, the mechanisms mediating this hyperemic response remain unknown. The cyclooxygenase pathway is active in skeletal muscle, is heat sensitive, and contributes to cutaneous thermal hyperemia in young healthy humans. Therefore, the purpose of this study was to test the hypothesis that cyclooxygenase inhibition would attenuate blood flow in the vastus lateralis muscle during localized heating. Twelve participants (6 women) were studied on two separate occasions: 1) time control (i.e., no ibuprofen); and 2) ingestion of 800 mg ibuprofen, a nonselective cyclooxygenase inhibitor. Experiments were randomized, counter-balanced, and separated by at least 10 days. Pulsed short-wave diathermy was used to induce unilateral deep heating of the vastus lateralis for 90 min, whereas the contralateral leg served as a thermoneutral control. Microdialysis was utilized to bypass the cutaneous circulation and directly measure local blood flow in the vastus lateralis muscle of each leg via the ethanol washout technique. Heat exposure increased muscle temperature and local blood flow (both P < 0.01 vs. baseline). However, the thermal hyperemic response did not differ between control and ibuprofen conditions (P ≥ 0.2). Muscle temperature slightly decreased for the thermoneutral leg (P < 0.01 vs. baseline), yet local blood flow remained relatively unchanged across time for control and ibuprofen conditions (both P ≥ 0.7). Taken together, our data suggest that inhibition of cyclooxygenase-derived vasodilator prostanoids does not blunt thermal hyperemia in skeletal muscle of young healthy humans.NEW & NOTEWORTHY Acute heat exposure increases skeletal muscle blood flow in humans. However, the mechanisms mediating this hyperemic response remain unknown. Using a pharmacological approach combined with microdialysis, we found that thermal hyperemia in the vastus lateralis muscle was well maintained despite the successful inhibition of cyclooxygenase. Our results suggest that cyclooxygenase-derived vasodilator prostanoids do not contribute to thermal hyperemia in skeletal muscle of young healthy humans.

Effects of temperature on viral load, inclusion body formation, and host response in Pacific Herring with viral erythrocytic necrosis (VEN).

OBJECTIVE: The primary objective of this study was to determine the effects of temperature on viral erythrocytic necrosis (VEN) progression under controlled conditions. Secondarily, this study was intended to evaluate the combined effects of temperature and VEN on the Pacific Herring Clupea palasii transcriptome. METHODS: The effects of temperature on VEN progression were assessed by waterborne exposure of laboratory-reared, specific-pathogen-free Pacific Herring to tissues homogenates containing erythrocytic necrosis virus (ENV) at 6.9, 9.0, or 13.5°C. RESULT: Exposure of Pacific Herring to ENV resulted in the establishment of infections characterized by high infection prevalence (89%; 40/45) and mean viral loads (5.5 log10 [gene copies/µg genomic DNA]) in kidney tissues at 44 days postexposure. Mean viral loads were significantly higher in fish from the ambient (mean = 9.0°C) and warm (mean = 13.5°C) treatments (6.1-6.2 log10 [gene copies/total genomic DNA]) than in fish from the cool (mean = 6.9°C) treatment (4.3 log10 [gene copies/µg genomic DNA]). Similarly, the peak proportion of diseased fish was directly related to temperature, with cytoplasmic inclusion bodies detected in 21% of fish from the cool treatment, 52% of fish from the ambient treatment, and 60% of fish from the warm treatment. The mean VEN load in each fish (enumerated as the percentage of erythrocytes with cytoplasmic inclusions) at 44 days postexposure increased with temperature from 15% in the cool treatment to 36% in the ambient treatment and 32% in the warm treatment. Transcriptional analysis indicated that the number of differentially expressed genes among ENV-exposed Pacific Herring increased with temperature, time postexposure, and viral load. Correlation network analysis of transcriptomic data showed robust activation of interferon and viral immune responses in the hepatic tissue of infected individuals independent of other experimental variables. CONCLUSION: Results from this controlled laboratory study, combined with previous observations of natural epizootics in wild populations, support the conclusion that temperature is an important disease cofactor for VEN in Pacific Herring.

An Examination of Occupational Therapy Telehealth Service Delivery Among Novice Users During the COVID-19 Pandemic.

The COVID-19 pandemic allowed for widespread implementation of telehealth as a delivery method for occupational therapy (OT) services. The purpose of this study was to investigate the perceptions of novice telehealth OT practitioners regarding telehealth as a delivery method for OT services. Quantitative data was collected through a modified version of the Telehealth Usability Questionnaire and analyzed via descriptive statistics. Qualitative data was collected by open-ended questions and analyzed via thematic analysis. OT practitioners' responses revealed four major themes: logistics of telehealth practice, role of client champions, capacity of the OT practitioner, and styles and approaches. The study revealed that OT sessions delivered via telehealth increased access to clients and continuity of services. Client champion engagement, effective coaching strategies, and practitioner flexibility supported the success of OT telehealth sessions.

A spatially resolved optical method to measure thermal diffusivity.

We describe an optical method to directly measure the position-dependent thermal diffusivity of reflective single crystal samples across a broad range of temperatures for condensed matter physics research. Two laser beams are used, one as a source to locally modulate the sample temperature, and the other as a probe of sample reflectivity, which is a function of the modulated temperature. Thermal diffusivity is obtained from the phase delay between source and probe signals. We combine this technique with a microscope setup in an optical cryostat, in which the sample is placed on a three-axis piezo-stage, allowing for spatially resolved measurements. Furthermore, we demonstrate experimentally and mathematically that isotropic in-plane diffusivity can be obtained when overlapping the two laser beams instead of separating them in the traditional way, which further enhances the spatial resolution to a micron scale, especially valuable when studying inhomogeneous or multidomain samples. We discuss in detail the experimental conditions under which this technique is valuable and demonstrate its performance on two stoichiometric bilayer ruthenates: Sr3Ru2O7 and Ca3Ru2O7. The spatial resolution allowed us to study the diffusivity in single domains of the latter, and we uncovered a temperature-dependent in-plane diffusivity anisotropy. Finally, we used the enhanced spatial resolution enabled by overlapping the two beams to measure the temperature-dependent diffusivity of Ti-doped Ca3Ru2O7, which exhibits a metal-insulator transition. We observed large variations of transition temperature over the same sample, originating from doping inhomogeneity and pointing to the power of spatially resolved techniques in accessing inherent properties.

Fate of Quasiparticles at High Temperature in the Correlated Metal Sr_{2}RuO_{4}.

We study the temperature evolution of quasiparticles in the correlated metal Sr_{2}RuO_{4}. Our angle resolved photoemission data show that quasiparticles persist up to temperatures above 200 K, far beyond the Fermi liquid regime. Extracting the quasiparticle self-energy, we demonstrate that the quasiparticle residue Z increases with increasing temperature. Quasiparticles eventually disappear on approaching the bad metal state of Sr_{2}RuO_{4} not by losing weight but via excessive broadening from super-Planckian scattering. We further show that the Fermi surface of Sr_{2}RuO_{4}-defined as the loci where the spectral function peaks-deflates with increasing temperature. These findings are in semiquantitative agreement with dynamical mean field theory calculations.

Species-specific in situ hybridization confirms arrested development of Henneguya ictaluri in hybrid catfish (Channel Catfish × Blue Catfish) under experimental conditions, with notes on mixed-species infections in clinical cases of proliferative gill disease from Mississippi catfish aquaculture.

OBJECTIVE: Proliferative gill disease (PGD) in Channel Catfish Ictalurus punctatus and hybrid catfish (Channel Catfish × Blue Catfish I. furcatus) is attributed to the myxozoan Henneguya ictaluri. Despite evidence of decreased H. ictaluri transmission and impaired parasite development in hybrid catfish, PGD still occurs in hybrid production systems. Previous metagenomic assessments of clinical PGD cases revealed numerous myxozoans within affected gill tissues in addition to H. ictaluri. The objective of this study was to investigate the development and pathologic contributions of H. ictaluri and other myxozoans in naturally and experimentally induced PGD. METHODS: Henneguya species-specific in situ hybridization (ISH) assays were developed using RNAscope technology. Natural infections were sourced from diagnostic case submissions in 2019. Experimental challenges involved Channel Catfish and hybrid catfish exposed to pond water from an active PGD outbreak, and the fish were sampled at 1, 7, 10, 12, 14, 16, 18, and 20 weeks postchallenge. RESULT: Nine unique ISH probes were designed, targeting a diagnostic variable region of the 18S ribosomal RNA gene of select myxozoan taxa identified in clinical PGD cases. Partial validation from pure H. ictaluri, H. adiposa, H. postexilis, and H. exilis infections illustrated species-specific labeling and no cross-reactivity between different myxozoan species or the catfish hosts. After experimental challenge, mature plasmodia of H. ictaluri and H. postexilis formed in Channel Catfish but were not observed in hybrids, suggesting impaired or delayed sporogenesis in the hybridized host. These investigations also confirmed the presence of mixed infections in clinical PGD cases. CONCLUSION: Although H. ictaluri appears to be the primary cause of PGD, presporogonic stages of other myxozoans were also present, which may contribute to disease pathology and exacerbate respiratory compromise by further altering normal gill morphology. This work provides molecular confirmation and more resolute developmental timelines of H. ictaluri and H. postexilis in Channel Catfish and supports previous research indicating impaired or precluded H. ictaluri sporogony in hybrid catfish.