Generation of a Broadly Useful Model for COVID-19 Pathogenesis, Vaccination, and Treatment.

COVID-19, caused by SARS-CoV-2, is a virulent pneumonia, with >4,000,000 confirmed cases worldwide and >290,000 deaths as of May 15, 2020. It is critical that vaccines and therapeutics be developed very rapidly. Mice, the ideal animal for assessing such interventions, are resistant to SARS-CoV-2. Here, we overcome this difficulty by exogenous delivery of human ACE2 with a replication-deficient adenovirus (Ad5-hACE2). Ad5-hACE2-sensitized mice developed pneumonia characterized by weight loss, severe pulmonary pathology, and high-titer virus replication in lungs. Type I interferon, T cells, and, most importantly, signal transducer and activator of transcription 1 (STAT1) are critical for virus clearance and disease resolution in these mice. Ad5-hACE2-transduced mice enabled rapid assessments of a vaccine candidate, of human convalescent plasma, and of two antiviral therapies (poly I:C and remdesivir). In summary, we describe a murine model of broad and immediate utility to investigate COVID-19 pathogenesis and to evaluate new therapies and vaccines.

Deficiency of FRMD5 results in neurodevelopmental dysfunction and autistic-like behavior in mice.

The pathophysiology of autism spectrum disorders (ASDs) is causally linked to postsynaptic scaffolding proteins, as evidenced by numerous large-scale genomic studies [1, 2] and in vitro and in vivo neurobiological studies of mutations in animal models [3, 4]. However, due to the distinct phenotypic and genetic heterogeneity observed in ASD patients, individual mutation genes account for only a small proportion (<2%) of cases [1, 5]. Recently, a human genetic study revealed a correlation between de novo variants in FERM domain-containing-5 (FRMD5) and neurodevelopmental abnormalities [6]. In this study, we demonstrate that deficiency of the scaffolding protein FRMD5 leads to neurodevelopmental dysfunction and ASD-like behavior in mice. FRMD5 deficiency results in morphological abnormalities in neurons and synaptic dysfunction in mice. Frmd5-deficient mice display learning and memory dysfunction, impaired social function, and increased repetitive stereotyped behavior. Mechanistically, tandem mass tag (TMT)-labeled quantitative proteomics revealed that FRMD5 deletion affects the distribution of synaptic proteins involved in the pathological process of ASD. Collectively, our findings delineate the critical role of FRMD5 in neurodevelopment and ASD pathophysiology, suggesting potential therapeutic implications for the treatment of ASD.

Two duplicated gsdf homeologs cooperatively regulate male differentiation by inhibiting cyp19a1a transcription in a hexaploid fish.

Although evolutionary fates and expression patterns of duplicated genes have been extensively investigated, how duplicated genes co-regulate a biological process in polyploids remains largely unknown. Here, we identified two gsdf (gonadal somatic cell-derived factor) homeologous genes (gsdf-A and gsdf-B) in hexaploid gibel carp (Carassius gibelio), wherein each homeolog contained three highly conserved alleles. Interestingly, gsdf-A and gsdf-B transcription were mainly activated by dmrt1-A (dsx- and mab-3-related transcription factor 1) and dmrt1-B, respectively. Loss of either gsdf-A or gsdf-B alone resulted in partial male-to-female sex reversal and loss of both caused complete sex reversal, which could be rescued by a nonsteroidal aromatase inhibitor. Compensatory expression of gsdf-A and gsdf-B was observed in gsdf-B and gsdf-A mutants, respectively. Subsequently, we determined that in tissue culture cells, Gsdf-A and Gsdf-B both interacted with Ncoa5 (nuclear receptor coactivator 5) and blocked Ncoa5 interaction with Rora (retinoic acid-related orphan receptor-alpha) to repress Rora/Ncoa5-induced activation of cyp19a1a (cytochrome P450, family 19, subfamily A, polypeptide 1a). These findings illustrate that Gsdf-A and Gsdf-B can regulate male differentiation by inhibiting cyp19a1a transcription in hexaploid gibel carp and also reveal that Gsdf-A and Gsdf-B can interact with Ncoa5 to suppress cyp19a1a transcription in vitro. This study provides a typical case of cooperative mechanism of duplicated genes in polyploids and also sheds light on the conserved evolution of sex differentiation.

Zebrafish MAP2K7 Simultaneously Enhances Host IRF7 Stability and Degrades Spring Viremia of Carp Virus P Protein via Ubiquitination Pathway.

During viral infection, host defensive proteins either enhance the host immune response or antagonize viral components directly. In this study, we report on the following two mechanisms employed by zebrafish mitogen-activated protein kinase kinase 7 (MAP2K7) to protect the host during spring viremia of carp virus (SVCV) infection: stabilization of host IRF7 and degradation of SVCV P protein. In vivo, map2k7+/- (map2k7-/- is a lethal mutation) zebrafish showed a higher lethality, more pronounced tissue damage, and more viral proteins in major immune organs than the controls. At the cellular level, overexpression of map2k7 significantly enhanced host cell antiviral capacity, and viral replication and proliferation were significantly suppressed. Additionally, MAP2K7 interacted with the C terminus of IRF7 and stabilized IRF7 by increasing K63-linked polyubiquitination. On the other hand, during MAP2K7 overexpression, SVCV P proteins were significantly decreased. Further analysis demonstrated that SVCV P protein was degraded by the ubiquitin-proteasome pathway, as the attenuation of K63-linked polyubiquitination was mediated by MAP2K7. Furthermore, the deubiquitinase USP7 was indispensable in P protein degradation. These results confirm the dual functions of MAP2K7 during viral infection. IMPORTANCE Normally, during viral infection, host antiviral factors individually modulate the host immune response or antagonize viral components to defense infection. In the present study, we report that zebrafish MAP2K7 plays a crucial positive role in the host antiviral process. According to the weaker antiviral capacity of map2k7+/- zebrafish than that of the control, we find that MAP2K7 reduces host lethality through two pathways, as follows: enhancing K63-linked polyubiquitination to promote host IRF7 stability and attenuating K63-mediated polyubiquitination to degrade the SVCV P protein. These two mechanisms of MAP2K7 reveal a special antiviral response in lower vertebrates.

Zebrafish TMEM47 is an effective blocker of IFN production during RNA and DNA virus infection.

IMPORTANCE: Mitochondrial antiviral signaling protein (MAVS) and stimulator of interferon (IFN) genes (STING) are key adaptor proteins required for innate immune responses to RNA and DNA virus infection. Here, we show that zebrafish transmembrane protein 47 (TMEM47) plays a critical role in regulating MAVS- and STING-triggered IFN production in a negative feedback manner. TMEM47 interacted with MAVS and STING for autophagic degradation, and ATG5 was essential for this process. These findings suggest the inhibitory function of TMEM47 on MAVS- and STING-mediated signaling responses during RNA and DNA virus infection.

Fish female-biased gene cyp19a1a leads to female antiviral response attenuation between sexes by autophagic degradation of MITA.

From insects to mammals, both innate and adaptive immune response are usually higher in females than in males, with the sex chromosome and hormonal differences considered the main reasons. Here, we report that zebrafish cyp19a1a (cytochrome P450, family 19, subfamily A, polypeptide 1a), an autosomal gene with female-biased expression, causes female fish to exhibit a lower antiviral response. First, we successfully constructed an infection model by intraperitoneal injection of spring viremia of carp virus (SVCV) into zebrafish (Danio rerio) and Carassius auratus herpesvirus (CaHV) in gibel carp (Carassius gibelio). Specifically, female fish were more vulnerable to viral infection than males, accompanied by a significantly weaker interferon (IFN) expression. After screening several candidates, cyp19a1a, which was highly expressed in female fish tissues, was selected for further analysis. The IFN expression and antiviral response were significantly higher in cyp19a1a-/- than in cyp19a1a+/+. Further investigation of the molecular mechanism revealed that Cyp19a1a targets mediator of IRF3 activation (MITA) for autophagic degradation. Interestingly, in the absence of MITA, Cyp19a1a alone could not elicit an autophagic response. Furthermore, the autophagy factor ATG14 (autophagy-related 14) was found interacted with Cyp19a1a to either promote or attenuate Cyp19a1a-mediated MITA degradation by either being overexpressed or knocked down, respectively. At the cellular level, both the normal and MITA-enhanced cellular antiviral responses were diminished by Cyp19a1a. These findings demonstrated a sex difference in the antiviral response based on a regulation mechanism controlled by a female-biased gene besides sex chromosome and hormonal differences, supplying the current understanding of sex differences in fish.

MRI-based Neuropathy Score Reporting And Data System (NS-RADS): multi-institutional wider-experience usability study of peripheral neuropathy conditions among 32 radiology readers.

OBJECTIVE: To determine the inter-reader reliability and diagnostic performance of classification and severity scales of Neuropathy Score Reporting And Data System (NS-RADS) among readers of differing experience levels after limited teaching of the scoring system. METHODS: This is a multi-institutional, cross-sectional, retrospective study of MRI cases of proven peripheral neuropathy (PN) conditions. Thirty-two radiology readers with varying experience levels were recruited from different institutions. Each reader attended and received a structured presentation that described the NS-RADS classification system containing examples and reviewed published articles on this subject. The readers were then asked to perform NS-RADS scoring with recording of category, subcategory, and most likely diagnosis. Inter-reader agreements were evaluated by Conger's kappa and diagnostic accuracy was calculated for each reader as percent correct diagnosis. A linear mixed model was used to estimate and compare accuracy between trainees and attendings. RESULTS: Across all readers, agreement was good for NS-RADS category and moderate for subcategory. Inter-reader agreement of trainees was comparable to attendings (0.65 vs 0.65). Reader accuracy for attendings was 75% (95% CI 73%, 77%), slightly higher than for trainees (71% (69%, 72%), p = 0.0006) for nerves and comparable for muscles (attendings, 87.5% (95% CI 86.1-88.8%) and trainees, 86.6% (95% CI 85.2-87.9%), p = 0.4). NS-RADS accuracy was also higher than average accuracy for the most plausible diagnosis for attending radiologists at 67% (95% CI 63%, 71%) and for trainees at 65% (95% CI 60%, 69%) (p = 0.036). CONCLUSION: Non-expert radiologists interpreted PN conditions with good accuracy and moderate-to-good inter-reader reliability using the NS-RADS scoring system. CLINICAL RELEVANCE STATEMENT: The Neuropathy Score Reporting And Data System (NS-RADS) is an accurate and reliable MRI-based image scoring system for practical use for the diagnosis and grading of severity of peripheral neuromuscular disorders by both experienced and general radiologists. KEY POINTS: • The Neuropathy Score Reporting And Data System (NS-RADS) can be used effectively by non-expert radiologists to categorize peripheral neuropathy. • Across 32 different experience-level readers, the agreement was good for NS-RADS category and moderate for NS-RADS subcategory. • NS-RADS accuracy was higher than the average accuracy for the most plausible diagnosis for both attending radiologists and trainees (at 75%, 71% and 65%, 65%, respectively).

Understanding and Mitigating Bias in Imaging Artificial Intelligence.

Artificial intelligence (AI) algorithms are prone to bias at multiple stages of model development, with potential for exacerbating health disparities. However, bias in imaging AI is a complex topic that encompasses multiple coexisting definitions. Bias may refer to unequal preference to a person or group owing to preexisting attitudes or beliefs, either intentional or unintentional. However, cognitive bias refers to systematic deviation from objective judgment due to reliance on heuristics, and statistical bias refers to differences between true and expected values, commonly manifesting as systematic error in model prediction (ie, a model with output unrepresentative of real-world conditions). Clinical decisions informed by biased models may lead to patient harm due to action on inaccurate AI results or exacerbate health inequities due to differing performance among patient populations. However, while inequitable bias can harm patients in this context, a mindful approach leveraging equitable bias can address underrepresentation of minority groups or rare diseases. Radiologists should also be aware of bias after AI deployment such as automation bias, or a tendency to agree with automated decisions despite contrary evidence. Understanding common sources of imaging AI bias and the consequences of using biased models can guide preventive measures to mitigate its impact. Accordingly, the authors focus on sources of bias at stages along the imaging machine learning life cycle, attempting to simplify potentially intimidating technical terminology for general radiologists using AI tools in practice or collaborating with data scientists and engineers for AI tool development. The authors review definitions of bias in AI, describe common sources of bias, and present recommendations to guide quality control measures to mitigate the impact of bias in imaging AI. Understanding the terms featured in this article will enable a proactive approach to identifying and mitigating bias in imaging AI. Published under a CC BY 4.0 license. Test Your Knowledge questions for this article are available in the supplemental material. See the invited commentary by Rouzrokh and Erickson in this issue.

Three-dimensional Volumetric Visceral and Subcutaneous Fat Analysis on Opportunistic Computed Tomography Imaging of Patients With Greater Trochanteric Pain Syndrome Compared With Those With Predominant Osteoarthritis: A Case-Control Study.

OBJECTIVE: This study aimed to address the gap in knowledge assessing the impact of visceral and subcutaneous body fat on 3-dimensional computed tomography imaging in patients with greater trochanteric pain syndrome (GTPS) in comparison with those primarily diagnosed with osteoarthritis (OA). MATERIALS AND METHODS: We evaluated adult patients with a confirmed diagnosis of GTPS from our institutional hip-preservation clinic spanning 2011 to 2022. Selection criteria included their initial clinic visit for hip pain and a concurrent pelvis computed tomography scan. These patients were age- and sex-matched to mild-moderate OA patients selected randomly from the database. Visceral and subcutaneous fat areas were measured volumetrically from the sacroiliac joint to the lesser trochanter using an independent software. Interreader reliability was also calculated. RESULTS: A total of 93 patients met the study criteria, of which 37 belonged to the GTPS group and 56 belonged to the OA group. Both groups were sex and race matched. Average age in GTPS and OA groups was 59.3 years and 56 years, respectively. For GTPS group, average body mass index was 28.9 kg/m 2 , and for the OA group, average body mass index was 29.9 kg/m 2 , with no significant difference ( P > 0.05). Two-sample t test showed no significant differences in the visceral fat, subcutaneous fat, or the visceral fat to total fat volume ratio between the GTPS and OA groups. There was excellent interreader reliability. CONCLUSIONS: Our results indicate that there is no significant difference in fat distribution and volumes among GTPS and OA patients. This suggests that being overweight or obese may not be directly linked or contribute to the onset of GTPS. Other factors, such as gluteal tendinopathy, bursitis, or iliotibial band syndrome, might be responsible and need further investigation.

Single-Plane 3-Dimensional Isotropic Spin-Echo Magnetic Resonance Imaging Reconstructions of Shoulder Exhibit Superior Correlation to Surgical Findings Than 2-Dimensional Dixon Multiplanar Magnetic Resonance Imaging.

OBJECTIVE: The aim of the study is to evaluate concordance of multiplanar 2-dimensional magnetic resonance imaging (2D-MRI) versus 3D isotropic MRI for rotator cuff and labral tears with the reference standard of arthroscopic surgical findings. METHODS: It was an institutional review board-approved retrospective single-center study of consecutive preoperative patients with isotropic 3D-MRI on 3-Tesla scanners, multiplanar 2D-MRI, and shoulder arthroscopy. Scapular plane-oriented contiguous multiplanar reconstructions of 3D-images were evaluated by 2 experienced fellowship-trained musculoskeletal radiologists. Variables included the following: labral tear presence and rotator-cuff tear Ellman grade, thickness, and width. Sensitivities (Sen) and specificities (Spe) were calculated for binary variables. Mean squared errors (MSE) were calculated for ordinal variables. Lower MSE indicated higher concordance. RESULTS: Seventy-two patients (43 female) with a mean age of 50.75 ± 9.76 years were evaluated. For infraspinatus-tear presence, 3D-MRI showed higher sensitivity (0.96) and specificity (0.68) than 2D-MRI (Sen = 0.85, Spe = 0.32) ( Psen = 0.005, Pspe = 0.002). For subscapularis-tear presence, 3D-MRI showed higher sensitivity (0.94) and specificity (0.73) compared with 2D-MRI (Sen = 0.83, Spe = 0.56) ( Psen = 0.02, Pspe = 0.04). For supraspinatus-tear presence, there was no significant difference between 3D-MRI (Sen =0.96, Spe = 0.67) compared with 2D-MRI (Sen = 0.98, Spe = 0.83) ( Psen = 0.43, Pspe = 0.63). For infraspinatus-tear thickness, 3D-MRI showed lower MSE (0.35) compared with 2D-MRI MSE (0.82) ( P = 0.01). For subscapularis-tear thickness, 3D-MRI had lower MSE (0.31) compared with 2D-MRI MSE (0.51) ( P = 0.007). However, no difference noted for supraspinatus-tear thickness when comparing 3D-MRI MSE (0.39) and 2D-MRI MSE (0.51) ( P = 0.49). For labral-tear presence, 3D-MRI had a lower MSE (0.20) compared with 2D-MRI MSE (0.57) ( P < 0.001). CONCLUSIONS: Three-dimensional MRI of the shoulder is time efficient with a shorter acquisition time and exhibits comparable with superior correlation to surgical findings than 2D-MRI for detection of labral tears and some rotator cuff tears. Three-dimensional MRI may be used in place of traditional 2D-MRI in detection of soft-tissue shoulder injury in centers equipped to do so.

Characterization of Demographical Histologic Diversity in Small Renal Masses With the Clear Cell Likelihood Score.

OBJECTIVE: This study aimed to develop a diagnostic model to estimate the distribution of small renal mass (SRM; ≤4 cm) histologic subtypes for patients with different demographic backgrounds and clear cell likelihood score (ccLS) designations. MATERIALS AND METHODS: A bi-institution retrospective cohort study was conducted where 347 patients (366 SRMs) underwent magnetic resonance imaging and received a ccLS before pathologic confirmation between June 2016 and November 2021. Age, sex, race, ethnicity, socioeconomic status, body mass index (BMI), and the ccLS were tabulated. The socioeconomic status for each patient was determined using the Area Deprivation Index associated with their residential address. The magnetic resonance imaging-derived ccLS assists in the characterization of SRMs by providing a likelihood of clear cell renal cell carcinoma (ccRCC). Pathological subtypes were grouped into four categories (ccRCC, papillary renal cell carcinoma, other renal cell carcinomas, or benign). Generalized estimating equations were used to estimate probabilities of the pathological subtypes across different patient subgroups. RESULTS: Race and ethnicity, BMI, and ccLS were significant predictors of histology (all P < 0.001). Obese (BMI, ≥30 kg/m 2 ) Hispanic patients with ccLS of ≥4 had the highest estimated rate of ccRCC (97.1%), and normal-weight (BMI, <25 kg/m 2 ) non-Hispanic Black patients with ccLS ≤2 had the lowest (0.2%). The highest estimated rates of papillary renal cell carcinoma were found in overweight (BMI, 25-30 kg/m 2 ) non-Hispanic Black patients with ccLS ≤2 (92.3%), and the lowest, in obese Hispanic patients with ccLS ≥4 (<0.1%). CONCLUSIONS: Patient race, ethnicity, BMI, and ccLS offer synergistic information to estimate the probabilities of SRM histologic subtypes.

Genomic anatomy of male-specific microchromosomes in a gynogenetic fish.

Unisexual taxa are commonly considered short-lived as the absence of meiotic recombination is supposed to accumulate deleterious mutations and hinder the creation of genetic diversity. However, the gynogenetic gibel carp (Carassius gibelio) with high genetic diversity and wide ecological distribution has outlived its predicted extinction time of a strict unisexual reproduction population. Unlike other unisexual vertebrates, males associated with supernumerary microchromosomes have been observed in gibel carp, which provides a unique system to explore the rationales underlying male occurrence in unisexual lineage and evolution of unisexual reproduction. Here, we identified a massively expanded satellite DNA cluster on microchromosomes of hexaploid gibel carp via comparing with the ancestral tetraploid crucian carp (Carassius auratus). Based on the satellite cluster, we developed a method for single chromosomal fluorescence microdissection and isolated three male-specific microchromosomes in a male metaphase cell. Genomic anatomy revealed that these male-specific microchromosomes contained homologous sequences of autosomes and abundant repetitive elements. Significantly, several potential male-specific genes with transcriptional activity were identified, among which four and five genes displayed male-specific and male-biased expression in gonads, respectively, during the developmental period of sex determination. Therefore, the male-specific microchromosomes resembling common features of sex chromosomes may be the main driving force for male occurrence in gynogenetic gibel carp, which sheds new light on the evolution of unisexual reproduction.

Deep learning generated lower extremity radiographic measurements are adequate for quick assessment of knee angular alignment and leg length determination.

PURPOSE: Angular and longitudinal deformities of leg alignment create excessive stresses across joints, leading to pain and impaired function. Multiple measurements are used to assess these deformities on anteroposterior (AP) full-length radiographs. An artificial intelligence (AI) software automatically locates anatomical landmarks on AP full-length radiographs and performs 13 measurements to assess knee angular alignment and leg length. The primary aim of this study was to evaluate the agreements in LLD and knee alignment measurements between an AI software and two board-certified radiologists in patients without metal implants. The secondary aim was to assess time savings achieved by AI. METHODS: The measurements assessed in the study were hip-knee-angle (HKA), anatomical-tibiofemoral angle (aTFA), anatomical-mechanical-axis angle (AMA), joint-line-convergence angle (JLCA), mechanical-lateral-proximal-femur-angle (mLPFA), mechanical-lateral-distal-femur-angle (mLDFA), mechanical-medial-proximal-tibia-angle (mMPTA), mechanical-lateral-distal-tibia- angle (mLDTA), femur length, tibia length, full leg length, leg length discrepancy (LLD), and mechanical axis deviation (MAD). These measurements were performed by two radiologists and the AI software on 164 legs. Intraclass-correlation-coefficients (ICC) and Bland-Altman analyses were used to assess the AI's performance. RESULTS: The AI software set incorrect landmarks for 11/164 legs. Excluding these cases, ICCs between the software and radiologists were excellent for 12/13 variables (11/13 with outliers included), and the AI software met performance targets for 11/13 variables (9/13 with outliers included). The mean reading time for the AI algorithm and two readers, respectively, was 38.3, 435.0, and 625.0 s. CONCLUSION: This study demonstrated that, with few exceptions, this AI-based software reliably generated measurements for most variables in the study and provided substantial time savings.

Unveiling adcyap1 as a protective factor linking pain and nerve regeneration through single-cell RNA sequencing of rat dorsal root ganglion neurons.

BACKGROUND: Severe peripheral nerve injury (PNI) often leads to significant movement disorders and intractable pain. Therefore, promoting nerve regeneration while avoiding neuropathic pain is crucial for the clinical treatment of PNI patients. However, established animal models for peripheral neuropathy fail to accurately recapitulate the clinical features of PNI. Additionally, researchers usually investigate neuropathic pain and axonal regeneration separately, leaving the intrinsic relationship between the development of neuropathic pain and nerve regeneration after PNI unclear. To explore the underlying connections between pain and regeneration after PNI and provide potential molecular targets, we performed single-cell RNA sequencing and functional verification in an established rat model, allowing simultaneous study of the neuropathic pain and axonal regeneration after PNI. RESULTS: First, a novel rat model named spared nerve crush (SNC) was created. In this model, two branches of the sciatic nerve were crushed, but the epineurium remained unsevered. This model successfully recapitulated both neuropathic pain and axonal regeneration after PNI, allowing for the study of the intrinsic link between these two crucial biological processes. Dorsal root ganglions (DRGs) from SNC and naïve rats at various time points after SNC were collected for single-cell RNA sequencing (scRNA-seq). After matching all scRNA-seq data to the 7 known DRG types, we discovered that the PEP1 and PEP3 DRG neuron subtypes increased in crushed and uncrushed DRG separately after SNC. Using experimental design scRNA-seq processing (EDSSP), we identified Adcyap1 as a potential gene contributing to both pain and nerve regeneration. Indeed, repeated intrathecal administration of PACAP38 mitigated pain and facilitated axonal regeneration, while Adcyap1 siRNA or PACAP6-38, an antagonist of PAC1R (a receptor of PACAP38) led to both mechanical hyperalgesia and delayed DRG axon regeneration in SNC rats. Moreover, these effects can be reversed by repeated intrathecal administration of PACAP38 in the acute phase but not the late phase after PNI, resulting in alleviated pain and promoted axonal regeneration. CONCLUSIONS: Our study reveals that Adcyap1 is an intrinsic protective factor linking neuropathic pain and axonal regeneration following PNI. This finding provides new potential targets and strategies for early therapeutic intervention of PNI.

Changes in Ploidy Drive Reproduction Transition and Genomic Diversity in a Polyploid Fish Complex.

Unisexual animals are commonly found in some polyploid species complexes, and most of these species have had a long evolutionary history. However, their method for avoiding genomic decay remains unclear. The polyploid Carassius complex naturally comprises the sexual amphidiploid C. auratus (crucian carp or goldfish) (AABB) and the gynogenetic amphitriploid C. gibelio (gibel carp) (AAABBB). Recently, we developed a fertile synthetic amphitetraploid (AAAABBBB) male from C. gibelio by incorporating a C. auratus genome. In this study, we generated novel amphitriploids (AAABBB) by backcrossing the amphitetraploid male with the amphidiploid C. auratus. Whole-genome resequencing revealed the genomic changes, including recombination and independent assortment between homologs of C. gibelio and C. auratus. The fertility, sex determination system, oocyte development, and fertilization behaviors of the novel amphitriploids were investigated. Approximately 80% of the novel amphitriploid females recovered the unisexual gynogenesis ability. Intriguingly, two types of primary oocyte (with and without homolog synapsis) were discovered, and their distinct development fates were observed. Type I oocytes entered apoptosis due to improper synaptonemal complex assembly and incomplete double-strand break repair, whereas subsequent type II oocytes bypassed meiosis through an alternative ameiotic pathway to develop into mature eggs. Moreover, gynogenesis was stabilized in their offspring, and a new array of diverse gynogenetic amphitriploid clones was produced. These revealed genomic changes and detailed cytological data provide comprehensive evidence that changes in ploidy drive unisexual and sexual reproduction transition, thereby resulting in genomic diversity and allowing C. gibelio avoid genomic decay.

MR Neurography of Lumbosacral Plexus: Incremental Value Over XR, CT, and MRI of L Spine With Improved Outcomes in Patients With Radiculopathy and Failed Back Surgery Syndrome.

BACKGROUND: Lower back pain is often evaluated using magnetic resonance imaging (MRI) and conventional imaging, which provide incomplete information about the etiology of pain and lead to less than optimal management. HYPOTHESIS: MR neurography (MRN) of the lumbosacral (LS) plexus renders a more accurate diagnosis, alters the management strategy, and clinical outcomes of radiculopathy or failed back surgery Syndrome (FBSS) patients when compared to the conventional imaging modalities. STUDY TYPE: Retrospective, cross-sectional. POPULATION: A total of 356 patients (mean age 65.8 ± 12.3; 48.9% female) from single university hospital over 6 years with MRN of LS plexus were included from a cohort of 14,775 total patients with lumbar spine MR imaging. ASSESSMENT: Conventional imaging obtained before and after MRN of LS plexus was reevaluated and categorized into three levels based on extent of imaging findings' correlation to presenting clinical symptoms (contributory levels). Clinical notes were reviewed for changes in ordering provider's recommended management and subsequent patients' symptom level pre-MRN to post-MRN. FIELD STRENGTH/SEQUENCE: A 5 T and 3.0 T. T1-weighted (T1W), T2-weighted (T2W), short T1 inversion recovery (STIR), T1 turbo spin echo (T1 TSE), T2 spectral attenuated inversion recovery (T2 SPAIR). STATISTICAL TESTS: Chi-squared test. Statistical significance was set at P < 0.05. RESULTS: A total of 356 total patients (174 females) with mean age ± SD was 65.8 ± 12.3 years, 4.2% of patients imaged with lumbar spine MRI. Definitely contributory studies among X-rays, computed tomography, MRI, and MRN were 3 of the 129 (2.3%), 3 of the 48 (6.2%), 35 of the 184 (19.0%), and 283 of the 356 (79.8%), respectively. Pre-MRN vs. post-MRN led to change in recommendation in 219 of the 356 (61.5%) patients and 71 of the 99 (71.7%) patients had improved symptoms. CONCLUSION: MRN of the LS plexus can provide more corroborative image findings for symptom correlation compared to other imaging modalities for accurate diagnosis, effects patient management and leads to positive clinical outcomes in a small subset of patients with radiculopathy or FBSS. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 5.

Diffusion-weighted MR imaging and utility of ADC measurements in characterizing nerve and muscle changes in diabetic patients on ankle DWI studies: a cross-sectional study.

OBJECTIVE: To evaluate the utility of apparent diffusion coefficient (ADC) measurements from ankle MRI diffusion-weighted imaging (DWI) studies in identifying neuropathic changes in diabetic patients. METHODS: In total, 109 consecutive ankle MRI scans (n = 101 patients) at a single tertiary care county hospital from November 1, 2019, to July 11, 2021, who met the inclusion criteria were identified. Patients were divided into 2 cohorts: diabetic (n = 62) and non-diabetic (n = 39). Demographics, HgbA1c, neuropathy diagnosis, and image quality data were collected. Abductor hallucis (AH) ADC mean and minimum (min) values and posterior tibial nerve (PTN) ADC mean and minimum values were measured. Student t-test and Pearson's correlation coefficient analysis were performed using R. RESULTS: Diabetic patients had significantly higher mean and min ADC values (× 10-3 mm2/s) of the AH muscle (mean: 1.77 vs 1.39, p < 0.001; min: 1.51 vs 1.06, p < 0.001) and PTN (mean: 1.65 vs 1.18, p < 0.001; min: 1.33 vs 0.95, p < 0.001) compared to non-diabetic patients. HgbA1c positively correlated with AH and PTN ADC mean values (AH: p = 0.036; PTN: p = 0.004). CONCLUSION: Our data suggests that an increasing diffusivity of water as quantified by ADC across neuronal and muscular membranes is a consequence of the pathophysiology of the disease. Thus, ankle MRI-DWI studies are useful in identifying neuropathic changes in diabetic patients and quantifying the severity noninvasively. KEY POINTS: • Diabetic patients had significantly higher mean and minimum ADC values of the abductor hallucis muscle and posterior tibial nerve compared to non-diabetic patients. • HgbA1c positively correlated with ADC mean values (AH: p = 0.036; PTN: p = 0.004) suggesting that an increasing diffusivity of water across neuronal and muscular membranes is a consequence of the pathophysiology of diabetic neuropathy. • Ankle MRI DWI can be used clinically to non-invasively identify neuropathic changes due to diabetes mellitus.

Extent of bone marrow edema on dual-energy CT aids in differentiation of acute from post-acute fractures of lower legs.

OBJECTIVES: Bone marrow edema (BME) from dual-energy CT is useful to direct attention to radiographically occult fractures. The aim was to characterize utility of BME of lower extremity (LE) fractures with the hypothesis that stabilized and post-acute fractures exhibit decreased extent and frequency of BME than non-stabilized and acute fractures, respectively. METHODS: An IRB-approved retrospective review of known LE fractures. A total of 141 cases met inclusion criteria, including 82 fractures without splint/cast stabilization, and 59 cases with stabilization. Two readers independently recorded BME, and its multiplicity and area (mm2). A separate reader assessed fracture location, comminution, and chronicity. Wilcoxon rank sum test, multiple regression, intraclass correlation (ICC), kappa statistics, and chi-square tests were used. RESULTS: BME was significantly larger in non-stabilized (859.3 mm2 (420.6-1451.8)) than stabilized fractures (493.5 mm2 (288.8-883.2)), p = .011). Comminuted (p = 0.006), non-stabilized (p = 0.0004), and acute fractures (p = 0.036) were all associated with larger BME area. BME presence had excellent results for both stabilized (Cohen's Kappa = 0.81) and non-stabilized fractures (Cohen's Kappa = 0.84). ICC for BME area showed excellent correlation for both stabilized (ICC = 0.78) and non-stabilized groups (ICC = 0.86). BME multiplicity showed excellent agreement for stabilized (ICC = 0.81) and good agreement for non-stabilized (ICC = 0.67) fractures. Lastly, stabilized cases showed increased multiplicity of BME compared to non-stabilized fractures (p < 0.001). CONCLUSIONS: BME evaluation can assist in differentiation of acute versus post-acute fractures. Extent of BME is reduced with splint/cast stabilization, which may limit its accuracy in detection of lower extremity fractures. KEY POINTS: • Evaluation of bone marrow edema on dual-energy CT aids in differentiation of acute versus post-acute fracture. • Bone marrow edema evaluation is limited in the setting of post-acute or stabilized fractures. • There is decreased frequency and extent of bone marrow edema in post-acute, non-comminuted, and stabilized fractures.

Diagnostic performance comparison of conventional radiography to magnetic resonance imaging for suspected osteomyelitis of the extremities: a multi-reader study.

OBJECTIVE: To determine whether MRI provides improved diagnostic accuracy compared to radiography for the diagnosis of extremity osteomyelitis (OM) with multi-reader analysis. METHODS: In this cross-sectional study, three musculoskeletal fellowship-trained expert radiologists evaluated cases of suspected OM in two rounds-first using radiographs (XR), then with conventional MRI. Radiologic features consistent with OM were recorded. Each reader recorded individual findings on both modalities and rendered a binary diagnosis along with certainty of final diagnosis on a confidence scale of 1-5. This was compared with the pathology-proven diagnosis of OM to determine diagnostic performance. Intraclass correlation (ICC) and Conger's Kappa were used for statistics. RESULTS: XR and MRIs of 213 pathology proven cases (51.5 years ± 14.0 years, mean ± St.Dev.) were included in this study, with 79 tested positive for OM and 98 were positive for a soft tissue abscess, with 78 patients being negative for both. In total, 139 were males and 74 females with bones of interest in the upper and lower extremities in 29 and 184 cases, respectively. MRI showed significantly higher sensitivity and negative predictive value than XR (p < 0.001 for both metrics). Conger's Kappa for OM diagnosis were 0.62 and 0.74 on XR and MRI, respectively. Reader confidence improved slightly from 4.54 to 4.57 when MRI was used. CONCLUSIONS: MRI is a diagnostically more effective imaging modality than XR for finding extremity osteomyelitis with better inter-reader reliability. CLINICAL RELEVANCE STATEMENT: This study validates the diagnosis of OM with MRI over XR but adds novelty because it is the largest study of its kind with a clear reference standard to guide clinician decision making. KEY POINTS: • Radiography is the first-line imaging modality for musculoskeletal pathology but MRI can add value for infections. • MRI shows greater sensitivity for the diagnosis of osteomyelitis of the extremities than radiography. • This improved diagnostic accuracy makes MRI a better imaging modality for patients with suspected osteomyelitis.

Comparison between ZOOMit DWI and conventional DWI in the assessment of foot and ankle infection: a prospective study.

OBJECTIVE: The study aimed to compare ZOOMit diffusion-weighted imaging (DWI) MRI with conventional DWI MRI for visualizing small bones in the foot, soft tissue abscesses, and osteomyelitis. MATERIALS AND METHODS: The cohort consisted of a consecutive series of patients with potential foot and ankle infections referred for MR imaging. Patients were imaged using both conventional and ZOOMit DWI in the same setting. Blinded reads were then conducted in separate settings and independent of known clinical diagnosis by two expert radiologists. The results from the reads were compared statistically using paired t-tests and with biopsy specimen analysis, both anatomopathological and microbiological. RESULTS: There was improvement in fat suppression using ZOOMit sequence compared to conventional DWI (p = .001) with no significant difference in motion artifacts (p = .278). ZOOMit had a higher rate of concordance with pathology findings for osteomyelitis (72%, 31/43 cases) compared with conventional DWI (60%, 26/43 cases). ZOOMit also identified 46 additional small bones of the foot and ankle (405/596, 68.0%) than conventional DWI (359/596, 60.2%). Conventional DWI however exhibited a more negative contrast-to-noise ratio (CNR) than ZOOMit (p = 0.001). CONCLUSION: ZOOMit DWI improves distal extremity proton diffusion assessment and helps visualize more bones in the foot, with less image distortion and improved fat saturation at the expense of reduced CNR. This makes it a viable option for assessing lower extremity infections. CLINICAL RELEVANCE STATEMENT: This study highlights the novel utilization of ZOOMit diffusion-weighted imaging (DWI) for the assessment of lower extremity lesions compared to conventional DWI. KEY POINTS: • Distal extremity diffusion-weighted imaging (DWI) is often limited. • ZOOMit DWI displayed improved fat suppression with less motion artifacts and better visualization of the lower extremity bones than conventional DWI. • ZOOMit shows decreased contrast-to-noise ratio than conventional DWI.