Thoracoscopic resection of lung masses is associated with excellent survival to discharge and good long-term outcomes.

OBJECTIVE: To report and evaluate risk factors for conversion and perioperative and long-term outcomes in dogs undergoing thoracoscopic lung lobectomy for resection of lung masses. ANIMALS: 61 client-owned dogs. METHODS: This retrospective cohort study (June 11, 2008, to February 14, 2020) of data collected from medical records included signalment, results of diagnostic imaging, surgical technique, surgical and anesthesia time, mass location and size, hospitalization time, histopathologic findings, and long-term outcome. Follow-up was obtained from medical records and telephone contact with owners or referring veterinarians. RESULTS: Histopathology results were available for 60 of 61 tumors. Fifty-seven (95%) were considered primary lung tumors, of which 46 (81%) were carcinomas. Clean surgical margins were achieved in 46 of 52 (88%) dogs. Conversion from thoracoscopy to thoracoscopic-assisted or open surgery occurred in 16 of 61 (26%) dogs. Larger tumor diameter (≥ 5 cm) and lymphadenopathy detected by preoperative CT scan were significantly associated with increased risk of conversion. There was no association between conversion and patient weight, body condition score, and tumor location. All 61 dogs survived to discharge, and 56 of 57 were alive 1 month postoperatively. Median overall survival time was 311 days (95% CI, 224 to 570 days). Tracheobronchial lymphadenopathy on preoperative CT scans was associated with shorter postoperative survival (P < .001). Patient age, tumor diameter, adjuvant chemotherapy following surgery, and incomplete margins were not associated with survival time. CLINICAL RELEVANCE: Dogs had high survival to discharge and good long-term prognosis following thoracoscopic lung lobectomy. However, larger tumor size and tracheobronchial lymphadenopathy may increase the likelihood of conversion.

The endoplasmic reticulum: Homeostasis and crosstalk in retinal health and disease.

The endoplasmic reticulum (ER) is the largest intracellular organelle carrying out a broad range of important cellular functions including protein biosynthesis, folding, and trafficking, lipid and sterol biosynthesis, carbohydrate metabolism, and calcium storage and gated release. In addition, the ER makes close contact with multiple intracellular organelles such as mitochondria and the plasma membrane to actively regulate the biogenesis, remodeling, and function of these organelles. Therefore, maintaining a homeostatic and functional ER is critical for the survival and function of cells. This vital process is implemented through well-orchestrated signaling pathways of the unfolded protein response (UPR). The UPR is activated when misfolded or unfolded proteins accumulate in the ER, a condition known as ER stress, and functions to restore ER homeostasis thus promoting cell survival. However, prolonged activation or dysregulation of the UPR can lead to cell death and other detrimental events such as inflammation and oxidative stress; these processes are implicated in the pathogenesis of many human diseases including retinal disorders. In this review manuscript, we discuss the unique features of the ER and ER stress signaling in the retina and retinal neurons and describe recent advances in the research to uncover the role of ER stress signaling in neurodegenerative retinal diseases including age-related macular degeneration, inherited retinal degeneration, achromatopsia and cone diseases, and diabetic retinopathy. In some chapters, we highlight the complex interactions between the ER and other intracellular organelles focusing on mitochondria and illustrate how ER stress signaling regulates common cellular stress pathways such as autophagy. We also touch upon the integrated stress response in retinal degeneration and diabetic retinopathy. Finally, we provide an update on the current development of pharmacological agents targeting the UPR response and discuss some unresolved questions and knowledge gaps to be addressed by future research.

Proteomic Analysis of Retinal Mitochondria-Associated ER Membranes Identified Novel Proteins of Retinal Degeneration in Long-Term Diabetes.

The mitochondria-associated endoplasmic reticulum (ER) membrane (MAM) is the physical contact site between the ER and the mitochondria and plays a vital role in the regulation of calcium signaling, bioenergetics, and inflammation. Disturbances in these processes and dysregulation of the ER and mitochondrial homeostasis contribute to the pathogenesis of diabetic retinopathy (DR). However, few studies have examined the impact of diabetes on the retinal MAM and its implication in DR pathogenesis. In the present study, we investigated the proteomic changes in retinal MAM from Long Evans rats with streptozotocin-induced long-term Type 1 diabetes. Furthermore, we performed in-depth bioinformatic analysis to identify key MAM proteins and pathways that are potentially implicated in retinal inflammation, angiogenesis, and neurodegeneration. A total of 2664 unique proteins were quantified using IonStar proteomics-pipeline in rat retinal MAM, among which 179 proteins showed significant changes in diabetes. Functional annotation revealed that the 179 proteins are involved in important biological processes such as cell survival, inflammatory response, and cellular maintenance, as well as multiple disease-relevant signaling pathways, e.g., integrin signaling, leukocyte extravasation, PPAR, PTEN, and RhoGDI signaling. Our study provides comprehensive information on MAM protein changes in diabetic retinas, which is helpful for understanding the mechanisms of metabolic dysfunction and retinal cell injury in DR.

Emerging roles of circular RNAs in retinal diseases.

Retinal disorders are a group of ocular diseases whose onset is associated with a number of aberrant molecular and cellular processes or physical damages that affect retinal structure and function resulting in neural and vascular degeneration in the retina. Current research has primarily focused on delaying retinal disease with minimal success in preventing or reversing neuronal degeneration. In this review, we explore a relatively new field of research involving circular RNAs, whose potential roles as biomarkers and mediators of retinal disease pathogenesis have only just emerged. While knowledge of circular RNAs function is limited given its novelty, current evidence has highlighted their roles as modulators of microRNAs, regulators of gene transcription, and biomarkers of disease development and progression. Here, we summarize how circular RNAs may be implicated in the pathogenesis of common retinal diseases including diabetic retinopathy, glaucoma, proliferative vitreoretinopathy, and age-related macular degeneration. Further, we explore the potential of circular RNAs as novel biomarkers and therapeutic targets for the diagnosis and treatment of retinal diseases.

Adult stem cells and niche cells segregate gradually from common precursors that build the adult Drosophila ovary during pupal development.

Production of proliferative follicle cells (FCs) and quiescent escort cells (ECs) by follicle stem cells (FSCs) in adult Drosophila ovaries is regulated by niche signals from anterior (cap cells, ECs) and posterior (polar FCs) sources. Here we show that ECs, FSCs, and FCs develop from common pupal precursors, with different fates acquired by progressive separation of cells along the AP axis and a graded decline in anterior cell proliferation. ECs, FSCs, and most FCs derive from intermingled cell (IC) precursors interspersed with germline cells. Precursors also accumulate posterior to ICs before engulfing a naked germline cyst projected out of the germarium to form the first egg chamber and posterior polar FC signaling center. Thus, stem and niche cells develop in appropriate numbers and spatial organization through regulated proliferative expansion together with progressive establishment of spatial signaling cues that guide adult cell behavior, rather than through rigid early specification events.

Analysis of risk factors associated with complications following mandibulectomy and maxillectomy in dogs.

OBJECTIVE: To provide information about complication rates and the risk factors for complications with mandibulectomy and maxillectomy procedures in dogs. ANIMALS: 459 client-owned dogs that underwent a mandibulectomy or maxillectomy between January 1, 2007, and January 1, 2018. PROCEDURES: Inclusion criteria included a complete medical record that contained an anesthesia record, surgical report, available histopathology results, and results of CBC and serum biochemical analysis before surgery. A minimum follow-up of 90 days after surgery was required. RESULTS: 271 complications occurred in 171 of 459 (37.3%) dogs. Eighteen complications were not given a severity description. Of the remaining 253 complications, most were considered minor (157/253 [62.1%]). Multivariable logistic regression analysis revealed that only increased surgical time had a significant (OR, 1.36; 95% CI, 1.12 to 1.54) association with the occurrence of ≥ 1 complication. For each additional hour of surgery, the odds of complications increased by 36%. Preoperative radiation therapy or chemotherapy increased the odds of incisional dehiscence or oral fistula formation (OR, 3.0; 95% CI, 1.3 to 7.2). Additionally, undergoing maxillectomy, compared with mandibulectomy, increased the odds of incisional dehiscence or oral fistula formation (OR, 1.8; 95% CI, 1.1 to 3.1). Two hundred forty-four of 271 (90.0%) complications occurred in the perioperative period (0 to 3 months after surgery). CONCLUSIONS AND CLINICAL RELEVANCE: Compared with mandibulectomy, performing maxillectomy increased the risk for incisional dehiscence or oral fistula formation. Mandibulectomy and maxillectomy had a moderate risk for a complication.

Evaluation of computer-aided design software methods for assessment of the three-dimensional geometry of the canine radius.

OBJECTIVE: To describe methods to measure the 3-D orientation of the proximal, diaphyseal, and distal segments of the canine radius by use of computer-aided design software (CADS) and to compare the repeatability and reliability of measurements derived by those methods. SAMPLE: 31 canine radii with biapical deformities and 24 clinically normal (control) canine radii. PROCEDURES: Select CT scans of radii were imported into a CADS program. Cartesian coordinate systems for the humerus and proximal, diaphyseal, and distal radial segments were developed. The orientation of each radial segment in the frontal, sagittal, and transverse planes was measured in triplicate by 3 methods. The repeatability and reliability of those measurements were calculated and compared among the 3 measurement methods. RESULTS: The mean ± SD within-subject repeatability of radial angular measurements for all 3 methods was 1.40 ± 0.67° in the frontal plane, 3.17 ± 2.21° in the sagittal plane, and 3.01 ± 1.11° in the transverse plane for control radii and 2.56 ± 1.95° in the frontal plane, 3.59 ± 2.39° in the sagittal plane, and 3.47 ± 1.19° in the transverse plane for abnormal radii. Mean ± SD bias between radial measurement methods was 1.88 ± 2.07° in the frontal plane, 6.44 ± 6.80° in the sagittal plane, and 2.27 ± 2.81° in the transverse plane. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that use of CADS to assess the 3-D orientation of the proximal, diaphyseal, and distal segments of normal and abnormal canine radii yielded highly repeatable and reliable measurements.

Comparative Analysis of Functional and Structural Decline in Retinitis Pigmentosas.

Retinitis pigmentosa (RP) is a category of inherited retinal dystrophies that is best prognosticated using electroretinography (ERG). In this retrospective cohort study of 25 patients with RP, we evaluated the correlation between 30 Hz flicker ERG and structural parameters in the retina. Internationally standardized 30 Hz flicker ERG recordings, short-wavelength autofluorescence (SW-AF), and spectral domain-optical coherence tomography (SD-OCT) were acquired at two visits at least one year apart. Vertical and horizontal hyperautofluorescent ring diameter measurements with SW-AF, as well as ellipsoid zone (EZ) line width measurements with SD-OCT, were used as structural parameters of disease progression. The 30 Hz flicker ERG amplitude decreased by 2.2 ± 0.8 µV/year (p = 0.011), while implicit times remained unchanged. For SD-OCT, the EZ line decreased by 204.1 ± 34.7 µm/year (p < 0.001). Horizontal and vertical hyperautofluorescent ring diameters decreased by 161.9 ± 25.6 µm/year and 146.9 ± 34.6 µm/year, respectively (p = 0.001), with SW-AF. A correlation was found between the progression rates of the 30 Hz flicker amplitude recorded with Burian-Allen electrodes and both the horizontal ring diameter (p = 0.020) and EZ line (p = 0.044). SW-AF and SD-OCT, two readily available imaging techniques, may be used to prognosticate disease progression because of the reliability of their measurements and correlation with functional outcome.

Reducing Medication Administration Frequency in Veteran Community Living Centers.

BACKGROUND: A quality improvement initiative of the Veterans Health Administration (VHA) aims to reduce frequency of medication administration to Veterans per day. Medication administration practices in our community living center (CLC) units are similar to an acute care medical unit versus a home environment. The objective of this project was to reduce medication administration frequency in order to minimize the number of interruptions to both Veterans and nurses. METHODS: A retrospective chart review was conducted for Veterans residing in a pilot CLC from January through March 2018. Electronic medical records and barcode medication administration (BCMA) logs were assessed. Data collected included demographic information and medication details (eg, drug name, frequency, administration time). Data were analyzed and pharmacist recommendations were documented into an Excel document, and then discussed with the pilot CLC unit medical provider in March 2018. The primary outcomes measured were the number and type of pharmacist recommendations, percent reduction in the average number of Veteran interruptions per day, and percent reduction in the average number of medication passes by nurse per day. RESULTS: Thirty-one Veterans were identified with a range of 4 to 31 active prescription orders. Fifty-five pharmacist recommendations were made and 31 were implemented. The average number of Veteran interruptions per day was reduced by 13.9%. The average daily number of medication passes was reduced by 16.3%. CONCLUSION: Both Veteran interruptions and nurse workload decreased due to the implemented pharmacist recommendations. Pharmacists will continue medication consolidation on a monthly basis and spread this project to other CLC units.

Compound heterozygous novel frameshift variants in the PROM1 gene result in Leber congenital amaurosis.

The PROM1 (prominin 1) gene encodes an 865-amino acid glycoprotein that is expressed in retinoblastoma cell lines and in the adult retina. The protein is localized to photoreceptor outer segment disc membranes, where it plays a structural role, and in the retinal pigment epithelium (RPE), where it acts as a cytosolic protein that mediates autophagy. Mutations in PROM1 are typically associated with cone-rod dystrophy 12 (OMIM#3612657), autosomal dominant retinal macular dystrophy 2 (OMIM#608051), autosomal recessive retinitis pigmentosa 41 (OMIM#612095), and Stargardt disease 4 (OMIM#603786). Here we describe the first case of PROM1-associated Leber congenital amaurosis (LCA) in a 12-yr-old Asian male, caused by two not previously described deleterious frameshift variants in the compound heterozygous state. Clinical features include the presence of bull's eye maculopathy, pendular horizontal nystagmus, and photodysphoria consistent with the clinical diagnosis of LCA. The patient was evaluated using ophthalmic imaging, electroretinography, and whole-exome sequencing. Electroretinography revealed extinguished retinal activity.

Hypoxic drive caused type 3 neovascularization in a preclinical model of exudative age-related macular degeneration.

Hypoxia associated with the high metabolic demand of rods has been implicated in the pathology of age-related macular degeneration (AMD), the most common cause of adult blindness in the developed world. The majority of AMD-associated severe vision loss cases are due to exudative AMD, characterized by neovascularization. To further investigate the causes and histopathology of exudative AMD, we conditionally induced hypoxia in a novel preclinical AMD model (Pde6gcreERT2/+;Vhl-/-) by targeting Vhl and used multimodal imaging and immunohistochemistry to track the development of hypoxia-induced neovascularization. In addition to developing a preclinical model that phenocopies exudative AMD, our studies revealed that the photoreceptor hypoxic response initiates and drives type 3 neovascularization, mainly in the outer retina. Activation of the VHL-HIF1a-VEGF-EPO pathway in the adult retina led to long-term neovascularization, retinal hemorrhages and compromised retinal layers. Our novel preclinical model would accelerate the testing of therapies that use metabolomic approaches to ameliorate AMD.

Pharmacist-Driven Step-Down of Long-Term Proton-Pump Inhibitor Therapy.

OBJECTIVE: To evaluate the appropriateness of proton-pump inhibitor (PPI) prescribing and reduce the number of outpatients on long-term PPI therapy, defined as greater than or equal to one year.
DESIGN: Phase I was retrospective and evaluated the appropriateness of PPI prescribing. Phase II was prospective and involved implementation of a pharmacist-driven PPI step-down protocol.
SETTING: This study was conducted in an outpatient setting at Veterans Affairs Hudson Valley Health Care System.
PATIENTS, PARTICIPANTS: Patients were limited to a single primary care provider and were required to fill an outpatient PPI prescription between August 15, 2015, and August 15, 2016.
INTERVENTIONS: After patients were identified in Phase I as having an inappropriate indication for long-term PPI therapy, they were contacted by a pharmacist to complete the step-down protocol. The patients then received a call two weeks after completing each step.
MAIN OUTCOME MEASURE(S): To determine the number of patients without an indication for long-term PPI therapy that could successfully complete the PPI step-down protocol.
RESULTS: Phase I identified that long-term PPI therapy was not indicated in 68.4% of patients. Phase II implementation demonstrated that 71.4% of patients were able to successfully step-down from PPI therapy in an average of 13 weeks with the use of alternative acid-suppression therapy.
CONCLUSION: This study concluded that a majority of PPI prescriptions were not indicated for a duration of greater than or equal to 1 year. With the implementation of a pharmacist-driven PPI step-down protocol, a majority of patients were able to tolerate the PPI step-down with the use of alternative acidsuppression therapy.

Multimodal structural disease progression of retinitis pigmentosa according to mode of inheritance.

We analyze disease progression in retinitis pigmentosa (RP) according to mode of inheritance by quantifying the progressive decrease of the ellipsoid zone (EZ) line width on spectral domain optical coherence tomography (SD-OCT) and of the dimensions of the hyperautofluorescent ring on short-wave fundus autofluorescence (SW-FAF). In this retrospective study of 96 patients, average follow-up time was 3.2 ± 1.9 years. EZ line width declined at a rate of -123 ± 8 µm per year, while the horizontal diameter and ring area declined at rates of -131 ± 9 µm and -0.5 ± 0.05 mm2 per year, respectively. Disease progression was found to be slowest for autosomal dominant RP and fastest for X-linked RP, with autosomal recessive RP progression rates between those of adRP and XLRP. EZ line width and ring diameter rates of disease progression were significantly different between each mode of inheritance. By using EZ line width and horizontal diameter as parameters of disease progression, our results confirm that adRP is the slowest progressing form of RP while XLRP is the fastest. Furthermore, the reported rates can serve as benchmarks for investigators of future clinical trials for RP and its different modes of inheritance.

Spectrum of Disease Severity and Phenotype in Choroideremia Carriers.

PURPOSE: To characterize and bring awareness to the disease spectrum of female choroideremia patients, as severity can vary from mild to severe disease, comparable to that observed in male patients. DESIGN: Retrospective cohort study. METHODS: Twelve female carriers of disease-causing variants in the CHM gene confirmed by molecular genetic sequencing were characterized clinically and imaged with short-wave fundus autofluorescence (SW-FAF), spectral-domain optical coherence tomography (OCT), and color fundus imaging. RESULTS: Twelve unrelated female patients with a clinical and genetic diagnosis of choroideremia carriers were included in this study. Disease severity among these phenotypes ranged from mild to severe, resembling the typical presentation of choroideremia in male patients. Mild disease presented with retinal pigment epithelium mottling, a patchy pattern of hypoautofluorescent speckles on SW-FAF, and intact retinal layers on spectral-domain OCT. Severe disease presented with widespread chorioretinal atrophy as shown by SW-FAF and spectral-domain OCT. Each of the identified genetic variants in CHM was predicted to be disease-causing according to in silico prediction software. Disease progression analysis of 4 patients with follow-up showed a decline in visual acuity for 2 patients, with progression observed on spectral-domain OCT in 1 of the patients. No significant disease progression on SW-FAF was observed for any of the patients. CONCLUSIONS: Female carriers of choroideremia can present with a wide range of clinical phenotypes and disease severity, from mild to severe disease, similar to male subjects. Symptomatic female subjects should be considered for current and upcoming gene replacement therapy clinical trials.

Mechanisms of neurodegeneration in a preclinical autosomal dominant retinitis pigmentosa knock-in model with a RhoD190N mutation.

D190N, a missense mutation in rhodopsin, causes photoreceptor degeneration in patients with autosomal dominant retinitis pigmentosa (adRP). Two competing hypotheses have been developed to explain why D190N rod photoreceptors degenerate: (a) defective rhodopsin trafficking prevents proteins from correctly exiting the endoplasmic reticulum, leading to their accumulation, with deleterious effects or (b) elevated mutant rhodopsin expression and unabated signaling causes excitotoxicity. A knock-in D190N mouse model was engineered to delineate the mechanism of pathogenesis. Wild type (wt) and mutant rhodopsin appeared correctly localized in rod outer segments of D190N heterozygotes. Moreover, the rhodopsin glycosylation state in the mutants appeared similar to that in wt mice. Thus, it seems plausible that the injurious effect of the heterozygous mutation is not related to mistrafficking of the protein, but rather from constitutive rhodopsin activity and a greater propensity for chromophore isomerization even in the absence of light.

Attenuation of Inherited and Acquired Retinal Degeneration Progression with Gene-based Techniques.

Inherited retinal dystrophies cause progressive vision loss and are major contributors to blindness worldwide. Advances in gene therapy have brought molecular approaches into the realm of clinical trials for these incurable illnesses. Select phase I, II and III trials are complete and provide some promise in terms of functional outcomes and safety, although questions do remain over the durability of their effects and the prevalence of inflammatory reactions. This article reviews gene therapy as it can be applied to inherited retinal dystrophies, provides an update of results from recent clinical trials, and discusses the future prospects of gene therapy and genome surgery.

Lung lobe torsion in dogs: 52 cases (2005-2017).

OBJECTIVE: To report outcomes and risk factors for mortality in dogs that underwent surgical management of lung lobe torsion. STUDY DESIGN: Retrospective case series from 5 veterinary teaching hospitals (2005-2017). ANIMALS: Fifty dogs with 52 instances of lung lobe torsion. METHODS: Data collected from medical records included signalment, clinical findings, results of clinicopathologic testing and diagnostic imaging, surgical treatment, lung lobe affected, intraoperative and postoperative complications, histopathologic and microbiologic findings, and outcome. Follow-up was obtained from medical records and telephone contact with primary care veterinarians. RESULTS: Fifty-two instances of lung lobe torsion were identified in 50 dogs, with a median follow-up of 453 days (range, 0-3075). Forty-six (92%) dogs survived to discharge. Dogs with concurrent torsion of the right cranial and middle lung lobes were less likely to survive (2/4) than those with torsion of the left cranial lung lobe (22/22). No other risk factors for mortality prior to hospital discharge were identified. Overall median survival time after hospital discharge was 1369 days. Four dogs had >1 episode of lung lobe torsion. CONCLUSION: The percentage of dogs surviving to discharge after surgical treatment of lung lobe torsion was higher than previously reported. The short- and long-term prognosis was excellent with surgical treatment of lung lobe torsion. CLINICAL SIGNIFICANCE: Surgery should be recommended when lung lobe torsion is suspected because of the high survival to discharge rate and excellent long-term prognosis.