Risk factors for corneal conjunctival grafting failure in dogs at four referral centers in the southern United States (203 patients): 2015-2021

OBJECTIVE

To report risk factors associated with conjunctival graft failure in dogs at four referral specialty centers.

PROCEDURES

Records of 203 dogs (229 eyes) undergoing conjunctival graft repair of ulcerative keratitis at four hospitals from 2015 to 2021 were reviewed. Success was defined as full graft integration with globe retention at the last postoperative evaluation; vision status was reported separately. Factors assessed included patient signalment, ophthalmic examination findings, surgical factors, and follow-up information.

RESULTS

Conjunctival graft failure occurred in 11% (25/229) of eyes and was significantly associated with ulcer depth, with corneal perforations having increased odds of graft failure compared with descemetoceles (odds ratio [OR] = 3.22, 95% confidence interval [CI] 1.11-9.32; p = .03) and stromal ulcers (OR = 10.89 [95% CI 1.38-86.18], p = .02). Brachycephalic dogs were significantly more likely than non-brachycephalic dogs to experience graft failure (OR = 5.02 [95% CI 1.42-17.74], p < .01). Surgery on the opposite eye relative to surgeon handedness was significantly associated with an increased risk of graft failure (OR 4.28 [95% CI 1.53-11.94], p < .01). The use of 7-0 and 8-0 suture versus 9-0 (p = .03) and the use of a combined simple continuous and interrupted pattern (p = .03) were significantly associated with an increased risk of graft failure. At the last follow-up, (median 61.5 days), 87% of dogs were visual.

CONCLUSIONS

Corneal perforations, surgery on the opposite eye relative to surgeon handedness, suture size and pattern, and brachycephalic conformation were significantly associated with an increased risk of graft failure in this study. These characteristics can be considered when determining prognosis for ulcerative keratitis requiring surgical intervention.

Practical and Ethical Guidelines for the Involvement of Trainees in Global Surgery: Consensus Statement and Recommendations from the Resident and Associate Society of the American College of Surgeons Global Surgery Work Group

BACKGROUND

The guidelines provided by US professional surgical organizations for involvement of trainees in global surgery are limited. The aim of this consensus statement is to provide surgical trainees with official recommendations from the Resident and Associate Society of the American College of Surgeons Global Surgery Work Group (GSWG) regarding professional, practical, and ethical guidelines for participation in global surgery endeavors.

STUDY DESIGN

A task force was created within the GSWG to review and define the scope of involvement of trainees in global surgery, and a consensus process was undertaken for the group at large to approve a set of proposed guidelines.

RESULTS

The list of practical and ethical guidelines for the engagement of trainees in global surgery covering the themes of preparedness, reciprocity and collaboration, ethical considerations, and sustainability was approved with consensus from the GSWG.

CONCLUSIONS

This consensus statement from the Resident and Associate Society of the American College of Surgeons GSWG outlines the official recommendations for guidelines for involvement of trainees in global surgery, with an aim to support equitable, sustainable collaborations that center on improving access to safe, timely, and affordable surgical care for the global community at large. Future processes seek to involve representation and perspectives from a larger body of low- to middle-income country surgical trainees.

Needs Assessment for a Resuscitative Thoracotomy Curriculum for General Surgery Residents in the Northeast Region

INTRODUCTION

Resuscitative thoracotomy (RT) is a high-acuity low occurrence (HALO) procedure with which general surgical resident (GSR) experience and confidence are unknown. We sought to identify and describe this educational gap by conducting a targeted needs assessment for an RT curriculum for GSRs.

METHODS

An online regional needs assessment survey was conducted for an RT curriculum for GSRs. The survey was developed by a group of trauma stakeholders and revised after being piloted on a small, representative group of GSRs. We surveyed GSRs in the Northeast region regarding their experience and confidence with RT; interest in an RT curriculum; and content, format, and scope for an RT curriculum.

RESULTS

The survey response rate was 43%, reflecting the viewpoints of GSRs at 8 major training centers across the Northeast. Only 13% of respondents were interested in pursuing a career in Trauma and Critical Care despite 97% of them training at a Level I Trauma Center. Twenty-nine percent and 33% of GSRs had ever assisted with or performed RT, respectively. Twenty-one percent of GSRs reported feeling confident performing RT. Most respondents (98%) agreed or strongly agreed that an RT curriculum would add value to their general surgery education. The most positively rated content topics were resuscitative maneuvers (100% positive responses [PR]), when to cease resuscitative efforts (100% PR), and morbidity and mortality associated with RT (98% PR). The most highly rated learning methods were individual RT simulation time (97% PR) and a tour of the trauma bay equipment (97% PR).

CONCLUSIONS

This needs assessment demonstrates a lack of experience and confidence with RT, a strong learner interest in an RT curriculum, and a desire for experiential learning methods. Learning objectives are defined herein, and the next steps involve developing educational materials for an RT curriculum for GSRs.

Alterations to the bovine bacterial ocular surface microbiome in the context of infectious bovine keratoconjunctivitis

BACKGROUND

Infectious bovine keratoconjunctivitis (IBK) is a common cause of morbidity in cattle, resulting in significant economic losses. This study aimed to characterize the bovine bacterial ocular surface microbiome (OSM) through conjunctival swab samples from Normal eyes and eyes with naturally acquired, active IBK across populations of cattle using a three-part approach, including bacterial culture, relative abundance (RA, 16 S rRNA gene sequencing), and semi-quantitative random forest modeling (real-time polymerase chain reaction (RT-PCR)).

RESULTS

Conjunctival swab samples were obtained from eyes individually classified as Normal (n = 376) or IBK (n = 228) based on clinical signs. Cattle unaffected by IBK and the unaffected eye in cattle with contralateral IBK were used to obtain Normal eye samples. Moraxella bovis was cultured from similar proportions of IBK (7/228, 3.07%) and Normal eyes (1/159, 0.63%) (p = 0.1481). Moraxella bovoculi was cultured more frequently (p < 0.0001) in IBK (59/228, 25.88%) than Normal (7/159, 4.40%) eyes. RA (via 16 S rRNA gene sequencing) of Actinobacteriota was significantly higher in Normal eyes (p = 0.0045). Corynebacterium variabile and Corynebacterium stationis (Actinobacteriota) were detected at significantly higher RA (p = 0.0008, p = 0.0025 respectively) in Normal eyes. Rothia nasimurium (Actinobacteriota) was detected at significantly higher RA in IBK eyes (p < 0.0001). Alpha-diversity index was not significantly different between IBK and Normal eyes (p > 0.05). Alpha-diversity indices for geographic location (p < 0.001), age (p < 0.0001), sex (p < 0.05) and breed (p < 0.01) and beta-diversity indices for geographic location (p < 0.001), disease status (p < 0.01), age (p < 0.001), sex (p < 0.001) and breed (p < 0.001) were significantly different between groups. Modeling of RT-PCR values reliably categorized the microbiome of IBK and Normal eyes; primers for Moraxella bovoculi, Moraxella bovis, and Staphylococcus spp. were consistently the most significant canonical variables in these models.

CONCLUSIONS

The results provide further evidence that multiple elements of the bovine bacterial OSM are altered in the context of IBK, indicating the involvement of a variety of bacteria in addition to Moraxella bovis, including Moraxella bovoculi and R. nasimurium, among others. Actinobacteriota RA is altered in IBK, providing possible opportunities for novel therapeutic interventions. While RT-PCR modeling provided limited further support for the involvement of Moraxella bovis in IBK, this was not overtly reflected in culture or RA results. Results also highlight the influence of geographic location and breed type (dairy or beef) on the bovine bacterial OSM. RT-PCR modeling reliably categorized samples as IBK or Normal.

Relationship between the bacterial ocular surface microbiota and outcomes for cats with feline herpesvirus type 1 ocular surface disease

OBJECTIVE

Feline herpesvirus 1 (FHV-1) causes ocular surface disease in domestic cats. The purpose of this study was to assess the relationship between bacterial ocular surface microbiota and outcomes for cats with FHV-1 ocular surface disease.

ANIMALS STUDIED

Twenty-two shelter-housed cats with confirmed FHV-1 ocular surface disease.

PROCEDURES

Animals were grouped according to FHV-1 shedding and ocular clinical scores following intervention: worsened outcome (WorOut, n = 11) or improved outcome (ImpOut, n = 11). Scoring and conjunctival sampling were completed on Days 1 and 8 of twice daily antiviral treatment. Bacterial DNA was extracted and submitted for 16S rRNA gene sequencing. Real-time polymerase chain reaction was performed for selected bacterial species. Overall DNA concentration between groups was assessed.

RESULTS

Bacterial microbiota relative abundance composition was significantly different between ImpOut and WorOut groups (weighted UniFrac p = .006). Alpha diversity was significantly higher in the ImpOut group compared with the WorOut group (Shannon p = .042, Simpson's p = .022, Pielou's p = .037). Differences in the relative abundance of various phyla and species were detected between groups. Total DNA concentration was higher in the WorOut group compared with the ImpOut group (p = .04). Feline GAPDH (p = .001) and Bilophila wadsworthia (p = .024) copy number was significantly higher in the ImpOut group compared with the WorOut group.

CONCLUSIONS

The results highlight the important relationship between the bacterial ocular surface microbiota and FHV-1 infection outcomes in cats treated with antiviral medications. Low bacterial species diversity, higher overall DNA (presumed predominantly bacterial) load, and certain bacterial phyla/species were associated with poor outcomes for cats with FHV-1 ocular disease.

Alterations of the bacterial ocular surface microbiome are found in both eyes of horses with unilateral ulcerative keratitis

Next generation sequencing (NGS) studies in healthy equine eyes have shown a more diverse ocular surface microbiota compared to culture-based techniques. This study aimed to compare the bacterial ocular surface microbiota in both eyes of horses with unilateral ulcerative keratitis (UK) with controls free of ocular disease. Conjunctival swabs were obtained from both ulcerated eyes and unaffected eyes of 15 client-owned horses with unilateral UK following informed consent, as well as from one eye of 15 healthy horses. Genomic DNA was extracted from the swabs and sequenced on an Illumina platform using primers that target the V4 region of bacterial 16S rRNA. Data were analyzed using Quantitative Insights Into Molecular Ecology (QIIME2). The ocular surface of ulcerated eyes had significantly decreased species richness compared with unaffected fellow eyes (Chao1 q = 0.045, Observed ASVs p = 0.045) with no differences in evenness of species (Shannon q = 0.135). Bacterial community structure was significantly different between either eye of horses with UK and controls (unweighted UniFrac: control vs. unaffected, p = 0.03; control vs. ulcerated, p = 0.003; unaffected vs. ulcerated, p = 0.016). Relative abundance of the gram-positive taxonomic class, Bacilli, was significantly increased in ulcerated eyes compared with controls (q = 0.004). Relative abundance of the taxonomic family Staphylococcaceae was significantly increased in ulcerated and unaffected eyes compared with controls (q = 0.030). The results suggest the occurrence of dysbiosis in infected eyes and reveal alterations in beta diversity and taxa of unaffected fellow eyes. Further investigations are necessary to better understand the role of the microbiome in the pathophysiology of ocular surface disease.

Clinical ophthalmic parameters of the Quaker parrot (Myiopsitta monachus)

PURPOSE

Ophthalmic diagnosis in many avian species remains hindered by a lack of normative values. This study aimed to establish normal ophthalmic parameters for select diagnostic tests in clinically normal Quaker parrots.

METHODS

Ninety-six captive Quaker parrots aged 8-18 years underwent ophthalmic examination to include assessment of neuro-ophthalmic reflexes, phenol red thread test, rebound tonometry, fluorescein staining, palpebral fissure length measurements, slit lamp biomicroscopy, indirect ophthalmoscopy, and ocular ultrasound biometry.

RESULTS

Menace response, dazzle reflex, and direct pupillary light reflex were present for all Quaker parrots. Tear production (mean ± SD) was 13.3 ± 4.0 mm/15 s and intraocular pressure (IOP, mean ± SD) was 10.6 ± 1.4 and 6.0 ± 1.3 mmHg in the D and P rebound tonometer calibration settings, respectively. For IOP measurement, D and P calibration settings were not interchangeable, with the lesser variation of the D setting preferred in the absence of a gold standard. Ultrasound measurement of the anterior chamber depth increased with age and males had longer axial globe and vitreous lengths. Incidental adnexal and ocular lesions, identified in 36/96 (37.5%) of Quaker parrots, did not statistically affect the created reference data.

CONCLUSIONS

This work provides reference values and clinical findings to assist with monitoring the health of wild populations and maintaining the health of captive Quaker parrots.

Relative and Quantitative Characterization of the Bovine Bacterial Ocular Surface Microbiome in the Context of Suspected Ocular Squamous Cell Carcinoma

The ocular surface microbiome is altered in certain disease states. The aim of this study was to characterize the bovine bacterial ocular surface microbiome (BBOSM) in the context of ocular squamous cell carcinoma (OSCC). The conjunctiva of normal (n = 28) and OSCC (n = 10) eyes of cows aged 2 to 13 years from two farms in Louisiana and Wyoming were sampled using individual sterile swabs. DNA extraction followed by 16S ribosomal ribonucleic acid (rRNA) gene sequencing and real-time polymerase chain reaction (RT-PCR) were performed to, respectively, assess the relative and absolute BBOSM. Discriminant analysis (DA) was performed using RT-PCR data, and relative abundance analysis was performed using 16S rRNA gene sequencing data. The 11 most abundant phyla in both normal and OSCC-affected cows were identified using 16S rRNA gene sequencing analysis. The relative abundance of Euryarchaeota was found to be significantly lower (p = 0.0372) in OSCC eyes compared to normal eyes. Relative abundance differences within and between geographic locations were also identified. Quadratic DA categorized samples as OSCC or normal with 100% sensitivity and 83.3-100% specificity. Relative abundance analysis identified relative BBOSM phylum alterations in OSCC. Quadratic DA can be used to accurately categorize BBOSM from normal and OSCC ocular surface samples.

Systemic Anti-Inflammatory Therapy Aided by Curcumin-Laden Double-Headed Nanoparticles Combined with Injectable Long-Acting Insulin in a Rodent Model of Diabetes Eye Disease

Therapeutic interventions that counter emerging targets in diabetes eye diseases are lacking. We hypothesize that a combination therapy targeting inflammation and hyperglycemia can prevent diabetic eye diseases. Here, we report a multipronged approach to prevent diabetic cataracts and retinopathy by combining orally bioavailable curcumin-laden double-headed (two molecules of gambogic acid conjugated to terminal carboxyl groups of poly(d,l-lactide-co-glycolide)) nanoparticles and injectable basal insulin. The combination treatment led to a significant delay in the progression of diabetic cataracts and retinopathy, improving liver function and peripheral glucose homeostasis. We found a concurrent reduction in lens aggregate protein, AGEs, and increased mitochondrial ATP production. Importantly, inhibition of Piezo1 protected against hyperglycemia-induced retinal vascular damage suggesting possible involvement of Piezo1 in the regulation of retinal phototransduction. Histologic evaluation of murine small intestines revealed that chronic administration of curcumin-laden double-headed nanoparticles was well tolerated, circumventing the fear of nanoparticle toxicity. These findings establish the potential of anti-inflammatory and anti-hyperglycemic combination therapy for the prevention of diabetic cataracts and retinopathy.

Paclitaxel and Urolithin A Prevent Histamine-Induced Neurovascular Breakdown Alike, in an Ex Vivo Rat Eye Model

Neurovascular eye problems are better prevented than managed or treated. Despite growing concern of occurrence in aging populations and development secondary to diseases such as diabetes and hypertension, we currently have very few options to tackle this global problem. Creating effective and high-throughput screening strategies is as important as the intervention itself. Here, we present for the first time a robust ex vivo rat eye model of histamine-induced vascular damage for investigating the therapeutic potential of paclitaxel (PTX) and urolithin A (UA) as alternatives to dexamethasone for preventing vascular damage in the retina. Extensive loss of vascularization and apoptosis were observed in the histamine-challenged group and successfully prevented in the intervention groups, more significantly in the PTX and UA. These important early results indicate that PTX and UA could be developed as potential preventive strategies for a wide variety of retinal diseases.

Patterns of General Surgery Residency Social Media Use in the Age of COVID-19

OBJECTIVE

The role for social media use by General Surgery departments continues to expand and social media accounts have been increasingly implemented as a tool for residency program for promotion and engagement. The importance of these accounts appears to have increased given the unprecedented changes with COVID-19 and the dramatic and unpredictable change to the application cycle including the use of virtual interviews, suggesting a perceived need for increased online engagement with applicants. The purpose of this study was to determine the patterns of creation and usage of Twitter and Instagram accounts of Accreditation Council for Graduate Medical Education (ACGME)-accredited General Surgery residency programs and their associated surgical departments.

METHORDS

A cross-sectional study of the use of Twitter and Instagram by the 332 ACGME-accredited General Surgery residency programs and their associated departments was conducted in February 2021. Twitter and Instagram accounts were identified by accessing program/department websites as well as social media platform and internet searches. Year of creation, number of followers, and number of posts (July 1, 2018-December 31, 2020) were collected. Trends in usage were compared across years stratified by platform and by account owner (department vs. residency).

RESULTS

Instagram accounts are more than five-times greater for residencies compared to departments (42% vs 8%, p < 0.001). There was not a significant difference between the number of department and residency Twitter accounts (26% vs 23%, p = 0.37). Significantly more residency Instagram and Twitter accounts were created or first posted in 2020 compared to department accounts (Instagram: 100 vs 7, p < 0.001; Twitter: 31 vs 6, p = 0.001). Over 18% of residency programs had both Twitter and Instagram accounts compared to only 6% of departments (p < 0.001). However, department Twitter and Instagram accounts had significantly higher median total posts from 7/1/2018-12/31/2020 (Twitter: p = 0.0001, Instagram p = 0.004). While the number of Instagram followers and accounts being followed were similar between residencies and departments, department Twitter accounts had a larger median number of followers (1141 vs. 430, p=0.003) and account followings (308 vs. 192, p = 0.001) compared to residency accounts.

CONCLUSIONS

The number of residency social media accounts has significantly increased in 2020 compared to account creation of departments, with Instagram account creation exceeding that of Twitter and of departments. The opposite pattern in usage was seen related to number of posts, and with Twitter, followers, and number of followings, with departments outpacing residencies. This significant increase in account creation may have been influenced by the COVID-19 pandemic and the change to a virtual interview season, suggesting an unprecedented need for online engagement with applicants. As the increased social media presence will likely persist in future application cycles, further study about the impact of residency social media use on recruitment and applicant decision-making as well as effective strategies, is needed.

Uveal Malignant Melanoma in a Hybrid Macaw Parrot (Ara chloropterus × Ara militaris)

An adult male green-winged (Ara chloropterus) × military (Ara militaris) hybrid macaw of unknown age was presented to the Texas A&M Veterinary Medical Teaching Hospital for evaluation of left periocular swelling, blepharospasm, and ocular discharge. Complete ophthalmic examination and B mode ocular ultrasonography were performed to evaluate the affected eye. Ocular examination revealed a blind left globe with exophthalmos, periocular swelling, diffuse corneal edema, and severe anterior fibrinous uveitis obscuring visualization of the intraocular structures. An ultrasound examination revealed a hyperechoic mass that filled the posterior segment of the globe. Focal discontinuity of the posterior sclera suggested scleral rupture. Enucleation with histopathology was recommended and performed 1.5 months later. Intraoperatively, a heavily pigmented and friable soft tissue mass extruded through the posterior sclera and extended into the orbit. Histologically, the mass was consistent with a malignant melanoma. The patient died 18 hours after the surgical procedure because of unknown complications. Postmortem examination did not identify evidence of metastasis. This study described the clinical appearance and histopathologic findings of a rare ocular neoplasm with extrascleral extension in a hybrid macaw. Although uncommon in psittacine birds, primary ocular melanocytic neoplasms may display features of malignancy with scleral or orbital invasion, or both.

A longitudinal surgical systems strengthening research program for medical students: the exploration of a model for global health education

BACKGROUND

In response to the staggering global burden of conditions requiring emergency and essential surgery, the development of international surgical system strengthening (SSS) is fundamental to achieving universal, timely, quality, and affordable surgical care. Opportunity exists in identifying optimal collaborative processes that both promote global surgery research and SSS, and include medical students. This study explores an education model to engage students in academic global surgery and SSS via institutional support for longitudinal research.

OBJECTIVES

We set out to design a program to align global health education and longitudinal health systems research by creating an education model to engage medical students in academic global surgery and SSS.

PROGRAM DESIGN AND IMPLEMENTATION

In 2015, medical schools in the United States and Colombia initiated a collaborative partnership for academic global surgery research and SSS. This included development of two longitudinal academic tracks in global health medical education and academic global surgery, which we differentiated by level of institutional resourcing. Herein is a retrospective evaluation of the first two years of this program by using commonly recognized academic output metrics.

MAIN ACHIEVEMENTS

In the first two years of the program, there were 76 total applicants to the two longitudinal tracks. Six of the 16 (37.5%) accepted students selected global surgery faculty as mentors (Acute Care Surgery faculty participating in SSS with Colombia). These global surgery students subsequently spent 24 total working weeks abroad over the two-year period participating in culminating research experiences in SSS. As a quantitative measure of the program's success, the students collectively produced a total of twenty scholarly pieces in the form of accepted posters, abstracts, podium presentations, and manuscripts in partnership with Colombian research mentors.

POLICY IMPLICATIONS

The establishment of scholarly global health education and research tracks has afforded our medical students an active role in international SSS through participation in academic global surgery research. We propose that these complementary programs can serve as a model for disseminated education and training of the future global systems-aware surgeon workforce with bidirectional growth in south and north regions with traditionally under-resourced SSS training programs.

Self-limiting Orbital Emphysema Following Ocular Evisceration and Demonstration of Nasolacrimal-Oropharyngeal Communication in a South African Ostrich (Struthio camelus australis)

A 25-year-old, male, sanctuary-owned, South African ostrich (Struthio camelus australis) was evaluated for orbital emphysema after evisceration of a nonvisual and chronically irritated eye. On initial ophthalmic examination, the ostrich's left eye displayed severe corneal fibrosis, broad anterior synechia, and a shallow anterior chamber, all suggestive of a previous corneal perforation. Conjunctival hyperemia and eyelid crusts were also present, reportedly associated with chronic rubbing. Evisceration of the left eye was performed by excising the eyelid margins, conjunctiva, nictitans, cornea, and intraocular contents. Four weeks postoperatively, a nonpainful, fluctuant swelling of the surgical site was noted. Trocarization of the surgical site verified orbital emphysema and served to temporarily decompress the orbit. Orbital emphysema reoccurred within 48 hours but gradually regressed without intervention over the subsequent 9 months. A Jones test was performed in the healthy, right eye and demonstrated clear communication to the oropharynx. To our knowledge, this is the first reported case of an evisceration performed on an ostrich and the first reported case of orbital emphysema in any avian species. It is probable that the emphysema noted in this case was secondary to nasolacrimal duct-oropharynx communication.

Traumatic Injury Under COVID-19 Stay-at-home Advisory: Experience of a New England Trauma Center

Background

With the onset of the COVID-19 pandemic and subsequent widespread stay-at-home advisories throughout early 2020, hospitals have noticed a decrease in illnesses unrelated to COVID-19. However, the impact on traumatic injury is relatively unknown. This study aims to characterize patterns of trauma during the COVID-19 pandemic at a Level I Trauma Center.

Materials & methods

A retrospective review was performed of adult trauma patients from March to June, in the years 2018 through 2020. Primary outcome was the number of trauma activations (volume). Secondary outcomes included activation level, mechanism of injury, mortality rate, and length of stay, and other demographic background. Trauma patterns of the 2018 and 2019 periods were combined as historical control, and compared to patterns of the biweekly-matched period of 2020.

Results

A total of 2,187 patients were included in analysis (Pre-COVID n = 1,572; COVID n = 615). Results were significant for decreased trauma volume but longer length of stay during COVID cohort, and for an increased proportion of males. No significant difference was found for other demographic variables, trauma mechanisms, or severity. Trauma volume patterns mirrored COVID rates in the state.

Conclusions

Despite a decline in trauma volume, other trauma patterns including severity and mechanism remained unchanged during the COVID-19 period. The decreased volume was not associated with a markedly lower clinical workload, change in team structure, or provider coverage re-distribution. Our data suggests that trauma volume and severity remained high enough during COVID-19 peak to necessitate full staffing, which may provide guidance in the event of a pandemic resurgence.

Analgesic effects of a retrobulbar block with 0.75% ropivacaine in dogs undergoing enucleation

OBJECTIVE

To assess the analgesic effects of a retrobulbar block with ropivacaine in dogs undergoing enucleation.

STUDY DESIGN

Prospective, randomized, masked placebo-controlled trial.

ANIMALS

A total of 23 client-owned dogs.

METHODS

Dogs were randomized to be administered a preoperative inferior-temporal palpebral retrobulbar injection of either ropivacaine 0.75% (1 mL 10 kg^-1; group RG) or equivalent volume of 0.9% saline (control; group CG). Intraoperative variables recorded to detect a response to noxious stimuli included heart rate (HR) and mean arterial pressure (MAP). Three observers assessed and recorded pain using a numerical rating pain scale and visual analog scale (VAS) before anesthesia (baseline) and postoperatively at 0, 0.5, 1, 2, 3, 4, 5, 6 and 24 hours after extubation. Rescue analgesia was administered if intraoperative HR or MAP increased by ≥ 20% from the previously recorded surgical time point, average postoperative pain scores totaled ≥ 9/20, scored ≥ 3/4 in any one category with VAS ≥ 35/100, or if VAS was ≥ 35/100 with a palpation score > 0/4.

RESULTS

Intraoperatively, there was no significant difference in HR or MAP between groups. Rescue analgesia was administered intraoperatively to four and one dogs and postoperatively to five and seven dogs in groups CG and RG, respectively, with no significant difference between groups. VAS scores were significantly lower in ropivacaine dogs at extubation (p = 0.02), but not at other postoperative time points. Adverse events were not observed in either group.

CONCLUSIONS AND CLINICAL RELEVANCE

Preoperative retrobulbar 0.75% ropivacaine injection (1 mL 10 kg^-1) provided analgesia in dogs following enucleation at extubation; however, intraoperative and postoperative pain control did not differ from a placebo injection with saline. Lack of differences between groups may have been influenced by sample size limitations.

Evaluation of the ocular surface mycobiota in clinically normal horses

The eye is host to myriad bacterial, fungal, and viral organisms that likely influence ocular surface physiology in normal and diseased states. The ocular surface mycobiota of horses has not yet been described using NGS techniques. This study aimed to characterize the ocular surface fungal microbiota (mycobiota) in healthy horses in 2 environmental conditions (stalled versus pasture). Conjunctival swabs of both eyes were obtained from 7 adult stallions stabled in an open-air pavilion and 5 adult mares living on pasture. Genomic DNA was extracted from ocular surface swabs and sequenced using primers that target the Internal Transcribed Spacer 1 (ITS1) region of the fungal genome on an Illumina platform. Sequences were processed using Quantitative Insights Into Molecular Ecology (QIIME 2.0) and taxonomy assigned with the Findley et al. 2013 ITS1 database. The most abundant genera identified were Leptosphaerulina (22.7%), unclassified Pleosporaceae (17.3%), Cladosporium (16.2%), Alternaria (9.8%), unclassified Pleosporales (4.4%), unclassified Montagnulaceae (2.9%), Fusarium (2.5%), and Pestalotiopsis (1.4%). Fungal community composition (Jaccard, R = 0.460, p = 0.001) and structure (Bray-Curtis, R = 0.811, p = 0.001) were significantly different between pastured mares and stabled stallions. The ocular surface of pastured mares had significantly increased fungal species richness and diversity compared to stabled stallions (Shannon p = 0.0224, Chao1 p = 0.0118, Observed OTUs p = 0.0241). Relative abundances of Aspergillus (p = 0.005) and Alternaria spp. (p = 0.002) were significantly increased in the mycobiota of pastured mares. This is the first report to describe the mycobiota of the equine ocular surface. Environmental factors such as housing influence the composition, structure, and richness of the equine ocular surface mycobiota.

Current ocular microbiome investigations limit reproducibility and reliability: Critical review and opportunities

Enthusiasm for research describing microbial communities using next-generation sequencing (NGS) has outpaced efforts to standardize methodology. Without consistency in the way research is carried out in this field, the comparison of data between studies is near impossible and the utility of results remains limited. This holds true for bacterial microbiome research of the ocular surface, and other sites, in both humans and animals. In addition, the ocular surface remains under-explored when compared to other mucosal sites. Low bacterial biomass samples from the ocular surface lead to further technical challenges. Taken together, two major problems were identified: (1) Normalization of the workflow in studies utilizing NGS to investigate the ocular surface bacteriome is necessary in order to propel the field forward and improve research impact through cross-study comparisons. (2) Current microbiome profiling technology was developed for high bacterial biomass samples (such as feces or soil), posing a challenge for analyses of samples with low bacterial load such as the ocular surface. This article reviews the challenges and limitations currently facing ocular microbiome research and provides recommendations for minimum reporting standards for veterinary ophthalmologists and clinician scientists to limit inter-study variation, improve reproducibility, and ultimately render results from these studies more impactful. The move toward normalization of methodology will expedite and maximize the potential for microbiome research to translate into meaningful discovery and tangible clinical applications.

First Precision Measurement of the Parity Violating Asymmetry in Cold Neutron Capture on ^{3}He

We report the first precision measurement of the parity-violating asymmetry in the direction of proton momentum with respect to the neutron spin, in the reaction ^{3}He(n,p)^{3}H, using the capture of polarized cold neutrons in an unpolarized active ^{3}He target. The asymmetry is a result of the weak interaction between nucleons, which remains one of the least well-understood aspects of electroweak theory. The measurement provides an important benchmark for modern effective field theory and potential model calculations. Measurements like this are necessary to determine the spin-isospin structure of the hadronic weak interaction. Our asymmetry result is A_{PV}=[1.55±0.97(stat)±0.24(sys)]×10^{-8}, which has the smallest uncertainty of any hadronic parity-violating asymmetry measurement so far.

Follicular choristoma in the third eyelid of an eclectus parrot (Eclectus roratus)

CASE DESCRIPTION

A 1-year-old male eclectus parrot (Eclectus roratus) with a 3- to 4-month history of blepharospasm in the right eye was referred to a veterinary medical teaching hospital for further evaluation. Conventional medical treatments had been ineffective. The referring avian specialist had plucked a suspected ectopic feather from the right eye 6 weeks prior to the referral evaluation.

CLINICAL FINDINGS

The parrot was sedated, and ophthalmic examination of the right eye with slit-lamp biomicroscopy revealed a 3 × 2 × 2-mm raised vascular mass with a focally pigmented center associated with the temporal aspect of the leading edge of the third eyelid. No abnormalities were detected in the left eye.

TREATMENT AND OUTCOME

The parrot was anesthetized, and the right eye mass was excised and submitted for histologic examination. Histologically, there was a single pigmented feather follicle bulb surrounded by multiple discrete lymphoid follicles and moderate lymphoplasmacytic inflammation within the substantia propria of the third eyelid conjunctiva. The histologically normal feather follicle in an abnormal location classified the lesion as a choristoma. Nine months after surgery, the parrot had no signs of ocular discomfort and no overt regrowth of the feather follicle.

CLINICAL RELEVANCE

For the eclectus parrot of this report, a lesion caused by normal differentiation of an ectopic feather follicle in the right third eyelid was successfully treated. A third eyelid choristoma appears to be a hitherto unreported pathological finding in avian species. Although rare, the presence of a choristoma should be considered as a differential diagnosis for birds with blepharospasm.

Feline ocular post-traumatic sarcomas: Current understanding, treatment and monitoring

PRACTICAL RELEVANCE

Ocular tumors in cats are seen uncommonly in general practice. Feline ocular post-traumatic sarcomas (FOPTS) represent a very aggressive type of ocular cancer that occurs in cats with a prior history of trauma or severe intraocular disease. Treatment options are limited and early recognition is imperative for close monitoring of disease progression and prompt enucleation.

CLINICAL CHALLENGES

There is often a delay between the initiating ocular trauma and tumor formation, with an average latency of approximately 6-7 years. Therefore, many cases may not be presented with a documented history of a traumatic incident, especially if the event occurred prior to adoption. While a histologic diagnosis is easy to obtain with enucleation, the aggressive and locally invasive behavior of FOPTS may prevent complete surgical resection.

GLOBAL IMPORTANCE

Cats are the most popular pet in the USA and Western Europe. As there is no breed predisposition for this particular cancer, and males are only slightly over-represented compared with females, a relatively large population of companion animals is at potential risk of developing FOPTS.

AUDIENCE

While uncommon, the understanding and recognition of this tumor type by general practitioners is important for the feline patient. This allows for close monitoring of cats known to have undergone serious ocular trauma, and prompt referral or early enucleation, as well as client education.

PATIENT GROUP

The typical patient is a middle-aged to older cat with a history of mechanical trauma to the eye, past intraocular surgery or chronic uveitis.

EVIDENCE BASE

Historically, there has been limited clinical evidence upon which to determine the optimal treatment for FOPTS, beyond enucleation of the affected eye. Recommendations are generally based on limited case reports and clinical experience of the practitioner.

Normative ocular data for juvenile and adult Japanese quail (Coturnix japonica)

OBJECTIVE

To obtain normative ocular data for Japanese quail as they mature from juveniles to adults.

ANIMALS STUDIED

Twenty-six captive Japanese quail comprising thirteen males and thirteen females, free of ocular disease, were included in the study.

PROCEDURES

Ophthalmic reference values were measured in both eyes at 1 and 5 months of age. A complete ophthalmic examination was performed, including neuro-ophthalmic reflexes, slit lamp biomicroscopy, phenol red thread test (PRTT), rebound tonometry, fluorescein staining, horizontal corneal diameter measurement, indirect ophthalmoscopy, and ocular ultrasound biometry. Ultrasound biomicroscopy measurements of axial globe length, lens thickness, vitreal chamber length, and pecten length were recorded. The depth of the anterior chamber was calculated by subtracting the lens thickness and vitreous length from the axial globe length. Measures of association and descriptive statistics were analyzed using STATA-14 and STATA-15.

RESULTS

Juvenile and adult females were heavier than age-matched males. Weight, intraocular pressure, horizontal corneal diameter, axial globe length, and lens thickness measurements increased with age. No statistically significant differences were found in the remainder of measurements among individuals in different sex or age-groups.

CONCLUSIONS

This work provides reference values and clinical findings that can be used in future research on quail and ocular disease.

Field effects studies in the Chernobyl Exclusion Zone: Lessons to be learnt

In the initial aftermath of the 1986 Chernobyl accident there were detrimental effects recorded on wildlife, including, mass mortality of pine trees close to the reactor, reduced pine seed production, reductions in soil invertebrate abundance and diversity and likely death of small mammals. More than 30 years after the Chernobyl accident there is no consensus on the longer-term impact of the chronic exposure to radiation on wildlife in what is now referred to as the Chernobyl Exclusion Zone. Reconciling this lack of consensus is one of the main challenges for radioecology. With the inclusion of environmental protection in, for instance, the recommendations of the International Commission on Radiological Protection (ICRP), we need to be able to incorporate knowledge of the potential effects of radiation on wildlife within the regulatory process (e.g. as a basis on which to define benchmark dose rates). In this paper, we use examples of reported effects on different wildlife groups inhabiting the Chernobyl Exclusion Zone (CEZ) as a framework to discuss potential reasons for the lack of consensus, consider important factors influencing dose rates organisms receive and make some recommendations on good practice.

Cactus-induced keratoconjunctivitis in Texas: A case series of three dogs and one cat

OBJECTIVE

To describe the historical, clinical, and diagnostic features of small animal patients affected by cactus-induced keratoconjunctivitis and their response to therapy.

ANIMALS STUDIED

Three dogs and one cat.

PROCEDURES

Ophthalmic examination directed subsequent selected diagnostic tests in each case including light microscopy of extracted foreign bodies, in vivo confocal microscopy (IVCM), corneal histopathology, and corneal bacterial culture. Treatments consisted of foreign body surgical extraction with concurrent medical therapy (three cases), or medical therapy alone (one case).

RESULTS

Clinical histories obtained supported acute cactus injury in all cases. Ophthalmic abnormalities were unilateral in each case and included ulcerative keratoconjunctivitis associated with linear, microscopic conjunctival and/or corneal penetrating cactus spines, known as glochids. Light microscopy and IVCM showed glochids to be heavily barbed, consistent with the spine morphology Prickly Pear (Opuntia) cactus species. Bacterial culture yielded Proprionicimonas sp. in one case with keratomalacia. Surgical extraction of spines was challenging, and residual conjunctival and/or corneal glochids were present in all cases. Patient discomfort resolved at a median of 21 days (range 10-51 days). Vision-threatening complications were not observed in any case at the time of last follow-up examination. Epithelial downgrowth, demonstrated by IVCM and histopathology, was present in one case at 108-day follow-up.

CONCLUSIONS

Cactus-induced keratoconjunctivitis should be considered as a differential in regions in which Opuntia cacti are prevalent, and microscopic ocular foreign bodies are observed. Although glochids are difficult to extract, positive clinical outcomes can occur in small animal patients despite the presence of residual organic corneal foreign material.

Effect of orally administered melatonin on intraocular pressure of ophthalmologically normal dogs

OBJECTIVE

To determine the effect of orally administered melatonin on the intraocular pressure (IOP) of ophthalmologically normal dogs.

ANIMALS

20 ophthalmologically normal dogs (40 eyes).

PROCEDURES

In a randomized crossover study, each dog received a 7-day regimen of melatonin (0.1 to 0.2 mg/kg, PO, q 12 h) and a placebo (150 mg of lactose powder in a capsule, PO, q 12 h), with a 7-day washout period between treatment regimens. Rebound tonometry was used to measure the IOP in both eyes of each dog 5 times at 2-hour intervals on days 0 (before administration of the first dose), 2, 4, and 7 (after administration of the last dose) of each treatment period. Repeated-measures ANOVA was used to evaluate the effects of treatment, day, and IOP measurement time within day on IOP.

RESULTS

Intraocular pressure was not significantly associated with treatment but was associated with day and the interaction between day and IOP measurement time within day. The mean ± SD IOP was 14.26 ± 2.95 and 14.34 ± 2.69 mm Hg for the melatonin and placebo regimens, respectively. Within each treatment period, the mean IOP tended to decrease from day 0 to 7 as well as within each day, which was attributed to the dogs becoming acclimated to the study protocol and natural diurnal variations in IOP.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that oral administration of melatonin (0.1 to 0.2 mg/kg, q 12 h for 7 d) did not significantly affect the IOP of ophthalmologically normal dogs.

Evaluation of the bacterial ocular surface microbiome in clinically normal horses before and after treatment with topical neomycin-polymyxin-bacitracin

Next generation sequencing (NGS) studies have demonstrated a rich and diverse ocular surface-associated microbiota in people that was previously undetected by traditional culture-based methods. The ocular surface microbiome of horses has yet to be investigated using NGS techniques. This study aimed to determine the bacterial composition of the ocular surface microbiome in healthy horses, and to identify whether there are microbial community changes over time and following topical antibiotic use. One eye of 12 horses was treated 3 times daily for 1 week with neomycin-polymyxin-bacitracin ophthalmic ointment. Contralateral eyes served as untreated controls. The inferior conjunctival fornix of both eyes was sampled at baseline prior to initiating treatment (day 0), after 1 week of treatment (day 7), and 4 weeks after concluding treatment (day 35). Genomic DNA was extracted from ocular surface swabs and sequenced using primers that target the V4 region of bacterial 16S rRNA. At baseline, the most abundant phyla identified were Proteobacteria (46.1%), Firmicutes (24.6%), Actinobacteria (12.6%), and Bacteroidetes (11.2%). The most abundant families included Pasteurellaceae (13.7%), Sphingomonadaceae (7.9%), an unclassified Order of Cardiobacteriales (7.7%), and Moraxellaceae (4.8%). Alpha and beta diversity measurements were unchanged in both treatment and control eyes over time. Overall, the major bacterial taxa on the equine ocular surface remained stable over time and following topical antibiotic therapy.

Canine ocular and periocular snakebites requiring enucleation: A report of 19 cases

PURPOSE

To describe the clinical and histopathologic features secondary to ocular and periocular snakebites in dogs requiring enucleation.

METHODS

Retrospective review of patients with recorded snakebite envenomation from the archives of the Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW) and Texas A&M Veterinary Medical Teaching Hospital (1997-2017). The cases included in this study required witnessed snakebites to the dog by the owner, clinical signs supportive of periocular or ocular envenomation, and/or histopathologic lesions compatible with snakebites. Two groups were established: ocular bites (OB) and periocular bites (PB).

RESULTS

Nineteen cases were included in the study (OB = 16/19; PB = 3/19). Dogs affected were typically older (median 8 years; range 1-18), and both sexes were equally represented. Left eyes (14/19) were more likely to sustain snake-induced trauma compared to right eyes (5/19). Fifteen breeds were identified, with terriers (9/19) commonly represented. Snakes bites occurred in six US states, with the majority of cases from Texas (7/19), California (5/19), and Arizona (4/19). Common clinical signs included facial edema, corneal ulceration, keratomalacia, uveitis, hyphema, and secondary glaucoma. All eyes demonstrated vision loss prior to enucleation. Histologically, the ocular and periocular tissues contained extensive necrosis associated with envenomation. Retinal detachment, lens capsule rupture, and intraocular hemorrhage/inflammation were commonly found.

CONCLUSIONS

Snakebite envenomation is a largely necrotizing disease process that can result in profound infiltrative and destructive ocular changes presumed to be related to the proteolytic factors and necrotoxins in venom. Ocular alterations secondary to snakebites may be irreversible regardless of supportive therapy instituted.

Evaluation of the bacterial ocular surface microbiome in clinically normal cats before and after treatment with topical erythromycin

The ocular surface microbiome of veterinary species has not been thoroughly characterized using next generation sequencing. Furthermore, alterations in the feline ocular surface microbiome over time or following topical antibiotic treatment are unknown. Aims of this study were to further characterize the ocular surface microbiome of healthy cats and to identify whether there are microbial community changes over time and following topical antibiotic use. Twenty-four eyes from twelve adult, research-bred, female spayed domestic shorthaired cats were evaluated. Erythromycin ophthalmic ointment (0.5%) was applied to the ocular surface of one randomly assigned eye per cat three times daily for 7 days, while the fellow eye served as an untreated control. The ocular surface was sampled by swabbing the inferior conjunctival fornix of both eyes prior to initiating treatment (day 0), after 1 week of treatment (day 7), and 4 weeks after concluding treatment (day 35). Genomic DNA was extracted from the swabs and sequenced using primers that target the V4 region of bacterial 16S rRNA genes. At baseline, the most common bacterial phyla identified were Proteobacteria (42.4%), Firmicutes (30.0%), Actinobacteria (15.6%), and Bacteroidetes (8.1%). The most abundant bacterial families sequenced were Corynebacteriaceae (7.8%), Helicobacteraceae (7.5%), Moraxellaceae (6.1%), and Comamonadaceae (5.6%). Alpha and beta diversity measurements were largely unchanged in both treatment and control eyes over time. However, univariate and linear discriminant analyses revealed significant and similar changes in the abundance of some bacterial taxa over time in both treatment and control eyes. Overall, the feline ocular surface microbiome remained stable over time and following topical antibiotic therapy.

Tropical Keratopathy (Florida Spots) in Cats

The authors used microscopy and synchrotron-based small-angle X-ray scattering analysis (SAXS) to describe lesions macroscopically typical of tropical keratopathy ("Florida spots") from 6 cats on St Kitts. Microscopically, there were varying degrees of epithelial hyperplasia and thinning of the cornea (by 4% to 18%) due to loss of corneal stroma associated with dense accumulations of collagen in the superficial stroma. The collagen fibrils in lesions were wider and had more variable diameters (39.5 ± 5.0 nm, mean ± SD) than in normal corneas (25.9 ± 3.6 nm; P < .01). There were occasional vacuoles (<1 μm) in the corneal epithelial basement membrane but no evidence of inflammation, edema, stromal neovascularization, fibrosis, acid-fast organisms, or structures suggestive of a fungal organism. SAXS analysis showed collagen fibril diameters and variation in size were greater in stroma containing the lesions compared to normal corneas (48.8 ± 4.5 nm vs 35.5 ± 2.6; P < .05). The d-spacing of collagen in the stroma of lesions and normal corneas was the same, but the average orientation index of collagen in lesions was greater (0.428 ± 0.08 vs 0.285 ± 0.03; P < .05). A survey revealed Florida spots lesions were static over time and became less obvious in only 1 of 6 affected cats adopted on St Kitts and taken to areas in the US where lesions are not reported. An anterior stromal collagen disorder with various degrees of epithelial hyperplasia is the pathologic hallmark of lesions clinically identical to Florida spots in cats from St Kitts.

Measuring pain in dogs and cats using structured behavioural observation

The contemporary approach to pain measurement in people and animals seeks to measure the affective (emotional) component of the pain experience using structured questionnaires with formal scoring methodology. Chronic pain has wide-ranging impacts which affects the quality of life (QOL) of the individual, whether that is a person or an animal. Accordingly instruments to measure chronic pain are designed to measure its impact on QOL and are called health-related quality of life (HRQL) instruments. In veterinary science instruments to measure pain are based on behavioural observation by the veterinary surgeon/nurse in the case of acute pain and by the owner in the case of chronic pain. The development of HRQL instruments is an expanding field in veterinary science, not just for the measurement of pain, but for other chronic diseases, and it has a wide application in pharmaceutical research and clinical practice to improve patient care. This review highlights the challenges involved in creating such measures for dogs and cats, seeking to provide the reader with an understanding of their development process. It then provides an overview of the current status with regard to acute and chronic pain measurement.

Andean surface uplift constrained by radiogenic isotopes of arc lavas

Climate and tectonics have complex feedback systems which are difficult to resolve and remain controversial. Here we propose a new climate-independent approach to constrain regional Andean surface uplift. ⁸⁷Sr/⁸⁶Sr and ¹⁴³Nd/¹⁴⁴Nd ratios of Quaternary frontal-arc lavas from the Andean Plateau are distinctly crustal (>0.705 and <0.5125, respectively) compared to non-plateau arc lavas, which we identify as a plateau discriminant. Strong linear correlations exist between smoothed elevation and ⁸⁷Sr/⁸⁶Sr (R² = 0.858, n = 17) and ¹⁴³Nd/¹⁴⁴Nd (R² = 0.919, n = 16) ratios of non-plateau arc lavas. These relationships are used to constrain 200 Myr of surface uplift history for the Western Cordillera (present elevation 4200 ± 516 m). Between 16 and 26°S, Miocene to recent arc lavas have comparable isotopic signatures, which we infer indicates that current elevations were attained in the Western Cordillera from 23 Ma. From 23–10 Ma, surface uplift gradually propagated southwards by ~400 km.

Multiple complex tectonic and climatic processes have formed the Andes, which today provides a unique ecological niche. Here, Scott et al. investigate how the chemical composition of lavas from stratovolcanoes can be used to give insight on the uplift of the Andes over the last 200 million years.

A transdiagnostic study of education, employment, and training outcomes in young people with mental illness

BACKGROUND

Optimizing functional recovery in young individuals with severe mental illness constitutes a major healthcare priority. The current study sought to quantify the cognitive and clinical factors underpinning academic and vocational engagement in a transdiagnostic and prospective youth mental health cohort. The primary outcome measure was 'not in education, employment or training' ('NEET') status.

METHOD

A clinical sample of psychiatric out-patients aged 15-25 years (n = 163) was assessed at two time points, on average, 24 months apart. Functional status, and clinical and neuropsychological data were collected. Bayesian structural equation modelling was used to confirm the factor structure of predictors and cross-lagged effects at follow-up.

RESULTS

Individually, NEET status, cognitive dysfunction and negative symptoms at baseline were predictive of NEET status at follow-up (p < 0.05). Baseline cognitive functioning was the only predictor of follow-up NEET status in the multivariate Bayesian model, while controlling for baseline NEET status. For every 1 s.d. deficit in cognition, the probability of being disengaged at follow-up increased by 40% (95% credible interval 19-58%). Baseline NEET status predicted poorer negative symptoms at follow-up (β = 0.24, 95% credible interval 0.04-0.43).

CONCLUSIONS

Disengagement with education, employment or training (i.e. being NEET) was reported in about one in four members of this cohort. The initial level of cognitive functioning was the strongest determinant of future NEET status, whereas being academically or vocationally engaged had an impact on future negative symptomatology. If replicated, these findings support the need to develop early interventions that target cognitive phenotypes transdiagnostically.

Overlap of abnormal photoreceptor development and progressive degeneration in Leber congenital amaurosis caused by NPHP5 mutation

Ciliary defects can result in severe disorders called ciliopathies. Mutations in NPHP5 cause a ciliopathy characterized by severe childhood onset retinal blindness, Leber congenital amaurosis (LCA), and renal disease. Using the canine NPHP5-LCA model we compared human and canine retinal phenotypes, and examined the early stages of photoreceptor development and degeneration, the kinetics of photoreceptor loss, the progression of degeneration and the expression profiles of selected genes. NPHP5-mutant dogs recapitulate the human phenotype of very early loss of rods, and relative retention of the central retinal cone photoreceptors that lack function. In mutant dogs, rod and cone photoreceptors have a sensory cilium, but develop and function abnormally and then rapidly degenerate; L/M cones are more severely affected than S-cones. The lack of outer segments in mutant cones indicates a ciliary dysfunction. Genes expressed in mutant rod or both rod and cone photoreceptors show significant downregulation, while those expressed only in cones are unchanged. Many genes in cell-death and -survival pathways also are downregulated. The canine disease is a non-syndromic LCA-ciliopathy, with normal renal structures and no CNS abnormalities. Our results identify the critical time points in the pathogenesis of the photoreceptor disease, and bring us closer to defining a potential time window for testing novel therapies for translation to patients.

Circadian clocks, obesity and cardiometabolic function

Life on earth is governed by the continuous 24-h cycle of light and dark. Organisms have adapted to this environment with clear diurnal rhythms in their physiology and metabolism, enabling them to anticipate predictable environmental fluctuations over the day and to optimize the timing of relevant biological processes to this cycle. These rhythms are regulated by molecular circadian clocks, and current evidence suggests that interactions between the central and peripheral molecular clocks are important in metabolic and vascular functions. Disrupting this process through mutations in the core clock genes or by interfering with the environmental zeitgebers that entrain the clock appear to modulate the function of cells and tissues, leading to an increased risk for cardiometabolic disease.

Spatially weighted functional clustering of river network data

Incorporating spatial covariance into clustering has previously been considered for functional data to identify groups of functions which are similar across space. However, in the majority of situations that have been considered until now the most appropriate metric has been Euclidean distance. Directed networks present additional challenges in terms of estimating spatial covariance due to their complex structure. Although suitable river network covariance models have been proposed for use with stream distance, where distance is computed along the stream network, these models have not been extended for contexts where the data are functional, as is often the case with environmental data. The paper develops a method of calculating spatial covariance between functions from sites along a river network and applies the measure as a weight within functional hierarchical clustering. Levels of nitrate pollution on the River Tweed in Scotland are considered with the aim of identifying groups of monitoring stations which display similar spatiotemporal characteristics.

Canine orbital rhabdomyosarcoma: a report of 18 cases

PURPOSE

To describe clinical and pathological features of canine orbital rhabdomyosarcoma (COR).

METHODS

Retrospective review of patients with COR from the archives of the Comparative Ocular Pathology Laboratory of Wisconsin and the University of Wisconsin Veterinary Medical Teaching Hospital (1983-2014).

RESULTS

Eighteen cases of COR were identified, all diagnosed in an 8-year period (2006-2014). Affected dogs were typically young (range 1-8; median 2 years), and both sexes were equally represented. Common clinical signs included exophthalmos (16/18) with dorsolateral deviation of the globe (10/18) and elevation of the nictitans (12/18). Ultrasonography, performed in nine cases, revealed an orbital mass with mixed echogenicity and posterior globe indentation. Advanced imaging, performed in nine cases, demonstrated a soft tissue mass with variable contrast enhancement and lysis of the orbital bones (5/9). Histologically, all tumors were subclassified as embryonal rhabdomyosarcoma. All neoplasms demonstrated positive immunohistochemical labeling for desmin, and 14/18 were positive for skeletal muscle actin. Follow-up information was available for 15/18 cases. Older dogs, aged 6-8 years, had no clinical signs of recurrence or metastasis 8-13 months postdiagnosis (4/4). Most younger dogs (9/11), aged 1-4 years, were euthanized within 6 months (median 2.5 months) of diagnosis due to recurrence at the surgical site (5/9) and/or metastasis (5/9).

CONCLUSIONS

Canine orbital rhabdomyosarcoma is a highly malignant neoplasm in juvenile dogs, but may be amenable to surgical resection in older dogs. This duality in biologic behavior may reflect differences in tissue of origin between juvenile onset tumors and adult onset tumors.