The Society of Thoracic Surgeons Expert Consensus Document on the Management of Pleural Drains following Pulmonary Lobectomy.

The Society of Thoracic Surgeons Workforce on Evidence Based Surgery provides this document on management of pleural drains following pulmonary lobectomy. The goal of this consensus document is to provide guidance regarding pleural drains in five specific areas: 1) choice of drain including size, type, and number, 2) management including use of suction versus water seal and criteria for removal, 3) imaging recommendations including the use of daily and post-pull chest x-rays, 4) use of digital drainage systems and 5) management of prolonged air leak. To formulate the consensus statements a task force of 15 general thoracic surgeons were invited to review the existing literature on this topic. Consensus was obtained using a modified Delphi method consisting of two rounds of voting until 75% agreement on the statements was reached. A total of thirteen consensus statements are provided to encourage standardization and stimulate additional research in this important area.

Assessment of tumor hypoxia in spontaneous canine tumors after treatment with OMX, a novel H-NOX oxygen carrier, with [18F]FMISO PET/CT.

BACKGROUND: Hypoxia is a detrimental factor in solid tumors, leading to aggressiveness and therapy resistance. OMX, a tunable oxygen carrier from the heme nitric oxide/oxygen-binding (H-NOX) protein family, has the potential to reduce tumor hypoxia. [18F]Fluoromisonidazole ([18F]FMISO) positron emission tomography (PET) is the most widely used and investigated method for non-invasive imaging of tumor hypoxia. In this study, we used [18F]FMISO PET/CT (computed tomography) to assess the effect of OMX on tumor hypoxia in spontaneous canine tumors. RESULTS: Thirteen canine patients with various tumors (n = 14) were randomly divided into blocks of two, with the treatment groups alternating between receiving intratumoral (IT) OMX injection (OMX IT group) and intravenous (IV) OMX injection (OMX IV group). Tumors were regarded as hypoxic if maximum tumor-to-muscle ratio (TMRmax) was greater than 1.4. In addition, hypoxic volume (HV) was defined as the region with tumor-to-muscle ratio greater than 1.4 on [18F]FMISO PET images. Hypoxia was detected in 6/7 tumors in the OMX IT group and 5/7 tumors in the OMX IV injection group. Although there was no significant difference in baseline hypoxia between the OMX IT and IV groups, the two groups showed different responses to OMX. In the OMX IV group, hypoxic tumors (n = 5) exhibited significant reductions in tumor hypoxia, as indicated by decreased TMRmax and HV in [18F]FMISO PET imaging after treatment. In contrast, hypoxic tumors in the OMX IT group (n = 6) displayed a significant increase in [18F]FMISO uptake and variable changes in TMRmax and HV. CONCLUSIONS: [18F]FMISO PET/CT imaging presents a promising non-invasive procedure for monitoring tumor hypoxia and assessing the efficacy of hypoxia-modulating therapies in canine patients. OMX has shown promising outcomes in reducing tumor hypoxia, especially when administered intravenously, as evident from reductions in both TMRmax and HV in [18F]FMISO PET imaging.

Discharge Opioid Dose Indirectly Associated With Functional Outcomes 2 Weeks After Shoulder and Knee Arthroscopy in a US Military Sample.

INTRODUCTION: Postsurgical opioid utilization may be directly and indirectly associated with a range of patient-related and surgery-related factors, above and beyond pain intensity. However, most studies examine postsurgical opioid utilization without accounting for the multitude of co-occurring relationships among predictors. Therefore, this study aimed to identify factors associated with opioid utilization in the first 2 weeks after arthroscopic surgery and examine the relationship between discharge opioid prescription doses and acute postsurgical outcomes. METHODS: In this prospective longitudinal observational study, 110 participants undergoing shoulder or knee arthroscopies from August 2016 to August 2018 at Walter Reed National Military Medical Center completed self-report measures before and at 14 days postoperatively. The association between opioid utilization and both patient-level and surgery-related factors was modeled using structural equation model path analysis. RESULTS: Participants who were prescribed more opioids took more opioids, which was associated with worse physical function and sleep problems at day 14, as indicated by the significant indirect effects of discharge opioid dose on day 14 outcomes. Additional patient-level and surgery-related factors were also significantly related to opioid utilization dose and day 14 outcomes. Most participants had opioid medications leftover at day 14. CONCLUSION: Excess opioid prescribing was common, did not result in improved pain alleviation, and was associated with poorer physical function and sleep 14 days after surgery. As such, higher prescribed opioid doses could reduce subacute functioning after surgery, without benefit in reducing pain. Future patient-centered studies to tailor opioid postsurgical prescribing are needed.

Preclinical evaluation and first-in-dog clinical trials of PBMC-expanded natural killer cells for adoptive immunotherapy in dogs with cancer.

BACKGROUND: Natural killer (NK) cells are cytotoxic cells capable of recognizing heterogeneous cancer targets without prior sensitization, making them promising prospects for use in cellular immunotherapy. Companion dogs develop spontaneous cancers in the context of an intact immune system, representing a valid cancer immunotherapy model. Previously, CD5 depletion of peripheral blood mononuclear cells (PBMCs) was used in dogs to isolate a CD5dim-expressing NK subset prior to co-culture with an irradiated feeder line, but this can limit the yield of the final NK product. This study aimed to assess NK activation, expansion, and preliminary clinical activity in first-in-dog clinical trials using a novel system with unmanipulated PBMCs to generate our NK cell product. METHODS: Starting populations of CD5-depleted cells and PBMCs from healthy beagle donors were co-cultured for 14 days, phenotype, cytotoxicity, and cytokine secretion were measured, and samples were sequenced using the 3'-Tag-RNA-Seq protocol. Co-cultured human PBMCs and NK-isolated cells were also sequenced for comparative analysis. In addition, two first-in-dog clinical trials were performed in dogs with melanoma and osteosarcoma using autologous and allogeneic NK cells, respectively, to establish safety and proof-of-concept of this manufacturing approach. RESULTS: Calculated cell counts, viability, killing, and cytokine secretion were equivalent or higher in expanded NK cells from canine PBMCs versus CD5-depleted cells, and immune phenotyping confirmed a CD3-NKp46+ product from PBMC-expanded cells at day 14. Transcriptomic analysis of expanded cell populations confirmed upregulation of NK activation genes and related pathways, and human NK cells using well-characterized NK markers closely mirrored canine gene expression patterns. Autologous and allogeneic PBMC-derived NK cells were successfully expanded for use in first-in-dog clinical trials, resulting in no serious adverse events and preliminary efficacy data. RNA sequencing of PBMCs from dogs receiving allogeneic NK transfer showed patient-unique gene signatures with NK gene expression trends in response to treatment. CONCLUSIONS: Overall, the use of unmanipulated PBMCs appears safe and potentially effective for canine NK immunotherapy with equivalent to superior results to CD5 depletion in NK expansion, activation, and cytotoxicity. Our preclinical and clinical data support further evaluation of this technique as a novel platform for optimizing NK immunotherapy in dogs.

Development of an Algorithm to Screen for Frailty Using the Clinical Frailty Scale with Postoperative Patients Entering Cardiac Rehabilitation.

Purpose: Frailty is not commonly assessed on intake to cardiac rehabilitation (CR), but screening could enable targeted interventions and potentially reduce secondary complications. This study aimed to develop and retrospectively examine the feasibility of utilizing a CR-specific algorithm based on the Clinical Frailty Scale (CFS). Our CFS-CR algorithm endeavoured to screen for frailty in older adults (> 65 y) entering CR following cardiac surgery/procedure. Method: The charts of 30 former patients (mean age: 74.0 ± 6.9 y) were examined by a clinician working in CR. Results: The clinician was unable to score any of the patients based on their medical charts using the CFS-CR due to insufficient data. Documentation was typically limited in the areas of instrumental and basic activities of daily living whereas exercise data were readily available. Conclusions: Current intake documentation in CR limited the ability to retrospectively screen for frailty. This finding suggests a need for a frailty-specific tool to support routine clinical screening. Prospective evaluation of the CFS-CR is warranted to further examine the clinical utility of the algorithm during CR intake assessments.

Objectif: la fragilité est peu évaluée à l'admission en réadaptation cardiaque (RC), mais le dépistage pourrait permettre de cibler des interventions et peutêtre de réduire les complications secondaires. La présente étude visait à créer un algorithme de RC d'après l'échelle de fragilité clinique (ÉFC) et à procéder à une analyse rétrospective pour déterminer la faisabilité de l'utiliser. L'algorithme ÉFC-RC était conçu pour dépister la fragilité chez les personnes âgées (de 65 ans ou plus) qui arrivaient en RC après une opération ou une intervention cardiaque. Méthodologie: une clinicienne qui travaillait en RC a examiné les dossiers de 30 anciens patients (âge moyen de 74,0 ± 6,9 ans). Résultats: la clinicienne n'a pu mesurer les résultats d'aucun patient d'après leur dossier médical au moyen de l'ÉFC-RC en raison de données insuffisantes. Les éléments du dossier se limitaient généralement aux activités déterminantes et courantes de la vie quotidienne, tandis que les données sur les exercices étaient facilement accessibles. Conclusions: l'information contenue dans les dossiers d'admission actuels en RC limitait la possibilité de procéder à l'analyse rétrospective de la fragilité. Cette observation laisse croire à la nécessité de concevoir un outil axé sur la fragilité pour contribuer au dépistage clinique systématique. Une évaluation prospective de l'ÉFC-RC s'impose pour mieux analyser l'utilité clinique de l'algorithme lors des évaluations à l'admission en RC.

Normal variation of clinical mobility of the mandibular symphysis in cats.

Introduction: The primary objective of this retrospective study was to document the normal variation of clinical mobility of the mandibular symphysis in cats and possible associations with bodyweight, age, sex, sexual status, breed and skull morphology. Secondarily, the radiographic appearance of the mandibular symphysis and possible associations with the analyzed data were evaluated. Materials and methods: Two hundred and sixteen cats of 15 different breeds that underwent maxillofacial, oral and dental procedures from April 2015 to December 2021 were included. Clinical mobility was evaluated under general anesthesia using a 0 to 3 scale in lateromedial (LM) and dorsoventral (DV) directions. The symphysis was radiographically classified on the occlusal radiographic view of the rostral mandibles as fused or open, and with parallel or divergent margins. Results: Bodyweight ranged from 2.2 to 12.5 kg (median 4.0 kg), age from 4 months to 17 years and 4 months (median 6 years and 4 months). At the first evaluation DV symphyseal mobility was 0 in 177 cases (82%), 1 in 32 cases (14.8%) and 2 in 7 cases (3.2%), LM mobility was 0 in 61 cases (28.3%), 1 in 110 cases (50.9%) and 2 in 45 cases (20.8%). 81.1% of the radiographs were included in the statistical analysis. Three symphyses (1.6%) were classified as fused and 190 (98.4%) as open, 129 (68.8%) having divergent margins and 61 (31.6%) parallel. One hundred and forty-eight cases (76.7%) did not show the presence of odontoclastic replacement resorption on the canine teeth (TR subgroup 1), 23 (11.9%) showed stage ≤3 lesions (TR subgroup 2) and 22 (11.4%) stage 4 lesions (TR subgroup 3). Logistic regression models exploring factors that affected DV and LM mobility were statistically significant (p < 0.0001; p < 0.0001) with an increase in LM mobility predicting an increase in DV mobility, and vice versa. An increase in DV mobility was associated with an increase in age and in having resorptive lesions. A decrease in LM symphyseal mobility was associated with being brachycephalic. Conclusion: The great majority of cases showed some degree of LM symphyseal mobility, and 18% showed DV mobility. Symphyseal bony fusion is rare but possible.

Submucosal tunneling endoscopic full-thickness resection for management of a rare case of esophageal GI stromal tumor.

Video 1The mass was identified at the upper- to mid-esophagus, 25 cm from the central incisors. No varices were seen on further examination of the esophagus. A 4-mm injector force needle was used to create a large submucosal injection using BlueBoost lifting agent proximal to the mass. A longitudinal mucosal incision was then made using the hybrid T-type electrocautery knife, 20 cm from the central incisors.The cutting current was the preset Endocut Q mode, and the coagulation setting was spray coag mode, effect 2 and 40 W.Next, tunnel creation by submucosal dissection was performed with a focus on keeping the submucosal space as clean as possible. Carbon dioxide was used for insufflation to prevent pneumoperitoneum.A smooth-surfaced oval mass was identified originating from the muscularis propria layer. Dissection was extended 2 cm distally beyond the mass. Next, resection of the mass was performed. First, the mucosal surface of the mass was dissected. Dissection began at the distal portion, proceeded to the left and right lateral borders, and then continued toward the proximal portion. The mass was dissected away from the muscularis propria.We focused on freeing the mass, ensuring this esophageal mass was intact throughout dissection. The attached bands of muscularis propria at the distal portion were carefully resected completely.Water irrigation was used at this time to ensure better visualization for resection. The remaining attached bands of muscularis propria were resected, ensuring complete en bloc resection. Afterward, the mass was suctioned into the cap and carefully retrieved as shown, and then sent to pathology for processing.The entire defect bed was inspected post-resection, and no perforation or bleeding was identified.The mucosal defect was completely closed with through-the-scope hemostatic clips in a longitudinal fashion beginning with approximation of the defect at the distal portion.

Improved characterization and translation of NK cells for canine immunotherapy.

The field of cancer immunology has seen a meteoric rise in interest and application due to the discovery of immunotherapies that target immune cells, often leading to dramatic anti-tumor effects. However, successful cellular immunotherapy for solid tumors remains a challenge, and the application of immunotherapy to dogs with naturally occurring cancers has emerged as a high yield large animal model to bridge the bench-to-bedside challenges of immunotherapies, including those based on natural killer (NK) cells. Here, we review recent developments in the characterization and understanding of canine NK cells, a critical springboard for future translational NK immunotherapy research. The characterization of canine NK cells is exceptionally pertinent given the ongoing challenges in defining them and contextualizing their similarities and differences compared to human and murine NK cells compounded by the limited availability of validated canine specific reagents. Additionally, we summarize the current landscape of the clinical and translational literature employing strategies to capitalize on endogenous and exogenous NK cell immunotherapy in canine cancer patients. The insights regarding efficacy and immune correlates from these trials provide a solid foundation to design and test novel combinational therapies to enhance NK cell activity with the added benefit of motivating comparative work to translate these findings to human cancers with extensive similarities to their canine counterparts. The compilation of knowledge from basic canine NK phenotype and function to applications in first-in-dog clinical trials will support the canine cancer model and enhance translational work to improve cancer outcomes for both dogs and humans.

Treatment of retroperitoneal sarcoma results in improved outcomes.

OBJECTIVE: To report the clinical characteristics, treatments, and outcomes in a cohort of dogs with histologically confirmed retroperitoneal sarcoma (RPS) and to identify potential variables of prognostic significance. ANIMALS: 46 client-owned dogs from 10 clinics with histopathologic diagnosis of a sarcoma originating from the retroperitoneal space. METHODS: Medical records were retrospectively reviewed to obtain information regarding clinical characteristics, treatments, and outcomes. Recorded variables were analyzed to report descriptive data for all cases and overall survival time. Multivariate analysis was utilized to evaluate prognostic factors for overall survival. RESULTS: Hemangiosarcoma was the most common histologic subtype diagnosed (76.1%). Cytoreductive and curative intent surgical excision of the RPS was attempted in 12 and 22 dogs, respectively; 12 dogs underwent no surgery or had an exploratory laparotomy with incisional biopsy only. Nineteen dogs received adjuvant chemotherapy, either injectable or metronomic, and 1 dog received adjuvant radiation therapy. Fourteen of the 34 (41.2%) surgically treated dogs developed evidence of local recurrence, but there was no difference in local recurrence when comparing dogs categorized as curative intent versus cytoreductive surgery. The median overall survival time was 238 days. On multivariable analysis, treatment approach was associated with survival with surgical excision (vs palliative treatment) and adjuvant chemotherapy following surgery being protective against death. A diagnosis of hemangiosarcoma was associated with a greater hazard of death. CLINICAL RELEVANCE: This study demonstrates a substantially greater survival time than previously published and suggests a survival benefit from surgical excision and adjuvant chemotherapy.

Aeromonas salmonicida, causative agent of salmonid furunculosis, isolated from the freshwater parasitic copepod, Salmincola californiensis.

Here, we provide evidence that the freshwater parasitic copepod, Salmincola californiensis, acts as a vector for Aeromonas salmonicida. While investigating the effects of S. californiensis on Chinoook salmon (Oncorhynchus tshawytscha), we tangentially observed that fish infected with the copepod developed furunculosis, caused by A. salmonicida. This occurred despite being reared in pathogen-free well water in a research facility with no prior history of spontaneous infection. We further investigated the possibility of S. californiensis to serve as a vector for the bacterium via detection of fluorescently labelled A. salmonicida inside the egg sacs from copepods in which the fish hosts were experimentally infected with GFP-A449 A. salmonicida. We then evaluated copepod egg sacs that were collected from adult Chinook salmon from a freshwater hatchery with A. salmonicida infections confirmed by either culture or PCR. The bacterium was cultured on tryptic soy agar plates from 75% of the egg sacs, and 61% were positive by PCR. These three separate experiments indicate an alternative tactic of transmission in addition to direct transmission of A. salmonicida in captivity. The copepod may play an important role in transmission of the bacterium when fish are more dispersed, such as in the wild.

A variant in the 5'UTR of ERBB4 is associated with lifespan in Golden Retrievers.

Genome-wide association studies (GWAS) in long-lived human populations have led to identification of variants associated with Alzheimer's disease and cardiovascular disease, the latter being the most common cause of mortality in people worldwide. In contrast, naturally occurring cancer represents the leading cause of death in pet dogs, and specific breeds like the Golden Retriever (GR) carry up to a 65% cancer-related death rate. We hypothesized that GWAS of long-lived GRs might lead to the identification of genetic variants capable of modifying longevity within this cancer-predisposed breed. A GWAS was performed comparing GR dogs ≥ 14 years to dogs dying prior to age 12 which revealed a significant association to ERBB4, the only member of the epidermal growth factor receptor family capable of serving as both a tumor suppressor gene and an oncogene. No coding variants were identified, however, distinct haplotypes in the 5'UTR were associated with reduced lifespan in two separate populations of GR dogs. When all GR dogs were analyzed together (n = 304), the presence of haplotype 3 was associated with shorter survival (11.8 years vs. 12.8 years, p = 0.024). GRs homozygous for haplotype 3 had the shortest survival, and GRs homozygous for haplotype 1 had the longest survival (11.6 years vs. 13.5 years, p = 0.0008). Sub-analyses revealed that the difference in lifespan for GRs carrying at least 1 copy of haplotype 3 was specific to female dogs (p = 0.009), whereas survival remained significantly different in both male and female GRs homozygous for haplotype 1 or haplotype 3 (p = 0.026 and p = 0.009, respectively). Taken together, these findings implicate a potential role for ERBB4 in GR longevity and provide evidence that within-breed canine lifespan studies could serve as a mechanism to identify favorable or disease-modifying variants important to the axis of aging and cancer.

Intestinal lesions and parasites associated with senescence and prespawn mortality in Chinook Salmon (Oncorhynchus tshawytscha).

Prespawn mortality (PSM) presents a major problem for the recovery of spring Chinook Salmon (Oncorhynchus tshawytscha) populations. In the Willamette River, Oregon, PSM exceeds 90% in some years but factors explaining it are not well understood. We examined intestinal tissue samples using histological slides from over 783 spring Chinook Salmon collected between 2009 and 2021, which included tissues from PSM fish, artificially spawned captive broodstock (BS) and normal river run fish, comprised of trapped (Live) and naturally post-spawned river (RPS) fish collected from the river. We observed degeneration of the intestinal epithelium and loss of villous structure, with concurrent severe enteritis. A natural progression of decline in epithelial integrity (EI) through the summer and fall until spawning and subsequent death was also observed. Live fish exhibited high EI scores (mean = 68%), BS exhibited variable EI scores (35%) and RPS exhibited severe loss of EI (14%). PSM fish exhibited prominent loss of intestinal epithelium with EI scores (13%), very similar to RPS fish, despite having been collected earlier in the year. Hence, we argue that low EI scores are strongly linked with PSM. Ceratonova shasta and Enterocytozoon schreckii were common in all groups, but neither were linked to either PSM or a decline in EI.

Have outcomes of trauma in centenarians changed in the last 15 years?

BACKGROUND: Centenarians are an often forgotten and under-reported group. Trauma in this population is a substantial cause of morbidity and mortality. 15 years ago, a small observational study examined the outcomes of trauma in centenarians in a single trauma unit, concluding that age alone should not be a determinant of treatment. Following implementation of national standards of care for trauma patients in older adults, this study re-examined outcomes in centenarians admitted secondary to trauma to assess if outcomes have changed. MATERIALS AND METHODS: We performed a retrospective cohort study examining patients aged over 100 years who had been admitted with trauma to an acute district general hospital and trauma unit. Patients were admitted from January 2020 to January 2022. Outcomes investigated included duration of hospital stay, complications, and mortality at three timepoints (inpatient, 30 days, 12 months). We compared this cohort to the cohort 15 years ago to assess for changes in outcomes. RESULTS: 29 patients met our eligibility criteria in this cohort. Common presenting injuries included hip fracture (13), pelvic ring fractures (8) and head injuries (8). There was significantly higher inpatient mortality within our cohort between patients who underwent operative versus non-operative treatment, but no significant difference in duration of hospital stay. There was no significant change in duration of hospital stay, inpatient mortality, or mortality at 30 days and 12 months between this cohort and 15 years ago. CONCLUSIONS: Outcomes of centenarians admitted secondary to trauma have been maintained but not improved in the last 15 years in our centre. Following this we must consider if more must be done to improve outcomes in this underreported but growing patient demographic.

Assessment of Oral Albendazole and Fumagillin in the Treatment of Pseudoloma neurophilia in Adult Zebrafish.

Pseudoloma neurophilia ( Pn ), the causative agent of the most commonly reported disease of zebrafish, is a microsporidian parasite that confounds research by inducing behavioral and physiologic changes in zebrafish. Although a treatment for P. neurophilia has not been documented in zebrafish, albendazole (ALB) and fumagillin (FUM) have been used to treat microsporidian infections of other fish species. To investigate the efficacy of oral ALB and FUM in the treatment of Pn, we performed a pilot study that demonstrated the safety and palatability of novel gel-based diets containing FUM or ALB in adult AB zebrafish. In a subsequent study, approximately 250 adult AB zebrafish (previously infected with Pn ) were treated with these medicated diets for 4 wk. At 4 different time points (weeks 0, 5, 10, and 16 of the study), fish were euthanized and whole-body qPCR was performed to assess Pn prevalence across treatment and control groups. There was no statistically significant association between treatment group and Pn prevalence at any time point, although potential biologically relevant reductions in Pn prevalence occurred in the combination therapy group at weeks 5 and 16 and in the ALB group at week 5. Based on high-performance liquid chromatography analyses, the medicated diets contained less ALB and more FUM than expected, highlighting the importance of validating medicated feed concentrations to ensure safety, efficacy, and consistency. While Pn remains challenging to eradicate and control, results of this study warrant further investigation into the utility of ALB and FUM as potential treatments for this pathogen.

Tenth Aquatic Models of Human Disease Conference 2022 Workshop Report: Aquatics Nutrition and Reference Diet Development.

Progress in biomedical research requires rigorous studies and reproducible outcomes. However, despite recent achievements, standard reference diets (SRDs) for aquatic model organisms, vital for supporting scientific rigor and reproducibility, are yet to be adopted. At this workshop, we presented findings from a 7-month diet test study, tightly coordinated and conducted across three aquatic research facilities: Zebrafish International Resource Center (ZIRC), Kent and Sharpton laboratories (Oregon State University), and Xiphophorus Genetic Stock Center (XGSC, Texas State University). We compared the impact of two commercial diets and a suggested zebrafish SRD on general fish husbandry, microbiome composition, and health in three fish species (zebrafish, Xiphophorus, and Medaka), and three zebrafish wild-type strains. We reported outcomes, gathered community feedback, and addressed the aquatic research community's need for SRD development. Discussions underscored the influence of diet on aquatic research variability, emphasizing the need for SRDs to control cross-experiment and cross-laboratory reproducibility. Species-specific reference diets are essential for model organism health and consistent research outcomes.

Normal variation of clinical mobility of the mandibular symphysis in dogs.

Introduction: The primary objective of this retrospective study was to document the normal variation of clinical mobility of the mandibular symphysis in dogs, and evaluate possible associations with breed, bodyweight, age, sex, and skull morphology. Secondarily, the radiographic appearance of the mandibular symphysis and possible associations with the analyzed data were also evaluated. Methods: Medical records of dogs that underwent anesthetic procedures for maxillofacial, oral and dental evaluation from April 2015 to December 2021 were included. Results: 567 dogs of 95 different breeds were included, with a total of 695 evaluations. Body weight ranged from 0.8 kg to 79 kg (median 14.4 kg) and age from 3 months to 16 years and 4 months (median 6 years and 9 months). Clinical mobility was evaluated under general anesthesia using a 0 to 3 scale, in lateromedial (LM) and dorsoventral (DV) directions. The symphysis was radiographically classified as being fused or open. The open symphyses were further radiographically divided in having parallel or divergent margins. At the time of the first evaluation DV mobility was 0 in 551 cases (97.2%) and 1 in 16 cases (2.8%). LM mobility was 0 in 401 cases (70.7%), 1 in 148 cases (26.1%) and 2 in 18 cases (3.2%). There was not a significant change in mobility over time for cases examined more than once (P= 0.76). All cases had an intraoral radiographic examination. 83.8% of the radiographs were included in the statistical analysis. Two symphyses (0.4%) were classified as fused and 473 (99.6%) as open, 355 (74.7%) having divergent margins and 118 (24.8%) parallel margins. Logistic regression models exploring factors that affected DV and LM mobility were statistically significant (P < 0.0001; P < 0.0001), with an increase in LM mobility predicting an increase in DV mobility, and vice versa. An increase in age and in bodyweight was associated with a decrease in mobility. There was no statistical difference in clinical mobility across specific breeds or sexes. Increased probability of a divergent symphysis and increased DV mobility was found to be associated with a brachycephalic conformation. The increase in LM mobility was comparatively higher in small brachycephalic breeds compared with larger brachycephalic breed. Discussion: The majority of the cases showed little to no mobility of the mandibular symphysis and radiographically bony fusion can be rarely seen.

Missing a "Missing Self" Mechanism: Modeling and Detection of Ly49 Expression in Canine NK Cells.

NK cells are a key focus in immuno-oncology, based on their ability to eliminate malignant cells without prior sensitization. Dogs are valuable models for translational immunotherapy studies, especially for NK cells, where critical species differences exist between mice and humans. Given that the mechanism for recognition of "self" by canine NK cells is currently unknown, we sought to evaluate expression of Ly49 in canine NK cells using in silico and high-throughput techniques. We interrogated the identified polymorphism/mutation in canine Ly49 and assessed the potential impact on structure using computational modeling of three-dimensional protein structure and protein-protein docking of canine Ly49 with MHC class I (MHC-I). Bulk and single-cell RNA-sequencing analysis was performed to detect gene expression of Ly49/KLRA1 in resting and activated NK cells. Tertiary protein structure demonstrated significant structural similarity to the known murine system. Molecular docking of canine Ly49 with MHC-I was favorable, converging at a single low-energy conformation. RNA sequencing revealed expression of Ly49/KLRA1 in both resting and activated NK cells and demonstrated almost exclusive expression of the gene in the NK cluster at the single-cell level. Despite prior reports of a mutated, nonfunctional canine Ly49, our data support that the protein product is predicted to bind to MHC-I in a comparable conformation to the murine system and is expressed in canine NK cells with upregulation following activation. Taken together, these data suggest that Ly49 is capable of recognizing MHC-I and therefore regulating NK cell function in dogs.

Training and validation of a novel non-invasive imaging system for ruling out malignancy in canine subcutaneous and cutaneous masses using machine learning in 664 masses.

Objective: To train and validate the use of a novel artificial intelligence-based thermal imaging system as a screening tool to rule out malignancy in cutaneous and subcutaneous masses in dogs. Animals: Training study: 147 client-owned dogs with 233 masses. Validation Study: 299 client-owned dogs with 525 masses. Cytology was non-diagnostic in 94 masses, resulting in 431 masses from 248 dogs with diagnostic samples. Procedures: The prospective studies were conducted between June 2020 and July 2022. During the scan, each mass and its adjacent healthy tissue was heated by a high-power Light-Emitting Diode. The tissue temperature was recorded by the device and consequently analyzed using a supervised machine learning algorithm to determine whether the mass required further investigation. The first study was performed to collect data to train the algorithm. The second study validated the algorithm, as the real-time device predictions were compared to the cytology and/or biopsy results. Results: The results for the validation study were that the device correctly classified 45 out of 53 malignant masses and 253 out of 378 benign masses (sensitivity = 85% and specificity = 67%). The negative predictive value of the system (i.e., percent of benign masses identified as benign) was 97%. Clinical relevance: The results demonstrate that this novel system could be used as a decision-support tool at the point of care, enabling clinicians to differentiate between benign lesions and those requiring further diagnostics.