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A personal narrative is presented which explores the author's experience of returning to his hometown of Huron, South Dakota, for his father's funeral.

Intrinsically photosensitive retinal ganglion cells (ipRGCs) play a crucial role in several physiological light responses. In this study, we generate an improved Opn4creknockin allele (Opn4cre(DSO)), which faithfully reproduces endogenous Opn4expression and improves compatibility with widely used reporters. We evaluated the efficacy and sensitivity of Opn4cre(DSO)for labeling in retina and brain and provide an in-depth comparison with the extensively utilized Opn4cre(Saha)line. Through this characterization, Opn4cre(DSO)demonstrated higher specificity in labeling ipRGCs with minimal recombination escape. Leveraging a combination of electrophysiological, molecular, and morphological analyses, we confirmed its sensitivity in detecting all ipRGC types (M1–M6) and defined their unique topographical distribution across the retina. In the brain, the Opn4cre(DSO)line labels ipRGC projections with minimal labeling of cell bodies. Overall, the Opn4cre(DSO)mouse line represents an improved tool for studying ipRGC function and distribution, offering a means to selectively target these cells to study light-regulated behaviors and physiology.

Symptomatic cervical spondylosis is a progressive degenerative condition of the cervical spine commonly resulting in functionally-limiting pain, weakness, and/or limited dexterity. Symptomatic cervical spondylosis is believed to occur at higher rates in military aviators than civilian counterparts and is a disqualifying condition for all Navy and Marine Corps aircrew. This condition is non-waiverable for tactical jet (ejection-seat-based) aviators. Medical attrition of experienced tactical jet aircrew from the military aviation community results in substantial cost to the U.S. Government, reduces fleet combat capability, and adversely impacts career progression and retention. The clinical maturation of cervical total disc replacement (TDR) technology over the last 2 decades has revolutionized the treatment of symptomatic cervical spondylosis and enabled a return to duty for hundreds of military service members in non-aviation fields. TDR studies demonstrate equal or superior functional outcomes, rates of symptom resolution, reduced complication and reoperation rates, and lower long-term cost compared to traditional Anterior Cervical Discectomy and Fusion (ACDF). Although initial computational modeling studies have evaluated cervical arthroplasty performance during rotary-wing crash impacts, safety within the dynamic tactical jet environment has not yet been established. The purpose of this article is to review factors relevant to TDR safety and outcomes and to propose a framework to evaluate the safety of TDR in Navy and Marine Corps tactical jet aircrew, to ultimately inform aeromedical algorithms regarding return to flight after TDR.

The opsin family of G-protein-coupled receptors are used as light detectors in animals. Opsin 5 (also known as neuropsin or OPN5) is a highly conserved opsin that is sensitive to visible violet light1,2. In mice, OPN5 is a known photoreceptor in the retina3and skin4but is also expressed in the hypothalamic preoptic area (POA)5. Here we describe a light-sensing pathway in which POA neurons that express Opn5regulate thermogenesis in brown adipose tissue (BAT). We show that Opn5is expressed in glutamatergic warm-sensing POA neurons that receive synaptic input from several thermoregulatory nuclei. We further show that Opn5POA neurons project to BAT and decrease its activity under chemogenetic stimulation. Opn5-null mice show overactive BAT, increased body temperature, and exaggerated thermogenesis when cold-challenged. Moreover, violet photostimulation during cold exposure acutely suppresses BAT temperature in wild-type mice but not in Opn5-null mice. Direct measurements of intracellular cAMP ex vivo show that Opn5POA neurons increase cAMP when stimulated with violet light. This analysis thus identifies a violet light-sensitive deep brain photoreceptor that normally suppresses BAT thermogenesis.

During mouse postnatal eye development, the embryonic hyaloid vascular network regresses from the vitreous as an adaption for high-acuity vision. This process occurs with precisely controlled timing. Here, we show that opsin 5 (OPN5; also known as neuropsin)-dependent retinal light responses regulate vascular development in the postnatal eye. In Opn5-null mice, hyaloid vessels regress precociously. We demonstrate that 380-nm light stimulation via OPN5 and VGAT (the vesicular GABA/glycine transporter) in retinal ganglion cells enhances the activity of inner retinal DAT (also known as SLC6A3; a dopamine reuptake transporter) and thus suppresses vitreal dopamine. In turn, dopamine acts directly on hyaloid vascular endothelial cells to suppress the activity of vascular endothelial growth factor receptor 2 (VEGFR2) and promote hyaloid vessel regression. With OPN5 loss of function, the vitreous dopamine level is elevated and results in premature hyaloid regression. These investigations identify violet light as a developmental timing cue that, via an OPN5–dopamine pathway, regulates optic axis clearance in preparation for visual function.

BACKGROUND AND OBJECTIVE:To report clinical feasibility of non-mydriatic ultra-widefield (NMUWF) imaging and determine the prevalence of peripheral retinal pathology in comparison to standard single-field imaging in a primary care setting.PATIENTS AND METHODS:Six hundred and thirty-two subjects (1,260 eyes) who underwent NMUWF imaging during annual health screening from October 2015 through March 2016 were retrospectively identified. An automated algorithm processed the raw images into: (1) NMUWF image with mask/grid outline that delineates the center 45° field simulating standard single-field photograph and (2) single-field image comprising 45° posterior pole extracted from the corresponding NMUWF image.RESULTS:Mean age of patients was 59.6 years ± 7.5 years. Of the 1,260 eyes, 1,238 eyes (98.3%) were considered optimum for grading. NMUWF images detected peripheral retinal pathology in 228 eyes (18.4%) that were not visible on corresponding single-field images.CONCLUSIONS:NMUWF imaging is feasible in a primary care setting, allows improved visualization of peripheral retinal pathology, and may therefore be useful for telemedicine screening.[[Ophthalmic Surg Lasers Imaging Retina. 2017;48:962–968.]

Long-term impacts of diet have been well studied; however, the immediate response of the intestinal epithelium to a change in nutrients remains poorly understood. We use physiological metrics and single-cell transcriptomics to interrogate the intestinal epithelial cell response to a high-fat diet (HFD). Within 1 day of HFD exposure, mice exhibit altered whole-body physiology and increased intestinal epithelial proliferation. Single-cell transcriptional analysis on day 1 reveals a cell-stress response in intestinal crypts and a shift toward fatty acid metabolism. By 3 days of HFD, computational trajectory analysis suggests an emergence of progenitors, with a transcriptional profile shifting from secretory populations toward enterocytes. Furthermore, enterocytes upregulate lipid absorption genes and show increased lipid absorption in vivoover 7 days of HFD. These findings demonstrate the rapid intestinal epithelial response to a dietary change and help illustrate the essential ability of animals to adapt to shifting nutritional environments.

Introduction:Cardiovascular (CV) risk prediction score have provided physicians with powerful screening and prevention tools.Hypothesis:In a large screening program of asymptomatic individuals, we sought to assess the CV risk reclassification provided by comparing multiethnic study on subclinical atherosclerosis-coronary artery calcium scoring (CACS) vs American Heart Association (AHA)-American College of Cardiology (ACC)-Atherosclerotic Cardiovascular Disease (ASCVD) score and Reynolds Risk Score (RRS).Methods:We included all 5324 patients (age 57± 8 years, 76% male and 87% white) who underwent CACS screening in a primary prevention clinic between 3/2016 and 10/2021. 10-year ASCVD, RRS and MESA-CACS scores were calculated and categorized as 0, 1-4.99%, 5-9.99% and ≥10%.Results:Mean MESA-CACS, ASCVD and RRS were 4.9± 5.6%, 6.6 ± 6.2%, and 4.5 ± 4.4%. A total of 2962 (56%) had a CAC of 0 of which 481 (16%) were on statin. MESA-CAC was moderately correlated with ASCVD and RRS (R= 0.65 and 0.62 respectively, both p<0.001, Figure 1a-b). Compared to ASCVD score, using MESA-CACS resulted in a downgraded risk in 1666 (31%) subjects, while 738 (14%) had an upgrade in risk. Similarly, compared to RRS, using MESA-CAC resulted in an upgraded risk in 797 (15%) and a downgrade in 1380 (26%) subjects. Additionally, 916 subjects (421 and 495 with an ASVCD score between 5-7.5 and 7.5-20% respectively) met criteria for statin therapy, but had CACS of 0, of which 234 (26%) were on a statin.Conclusions:Utilization of MESA-CACS in primary prevention results insignificant reclassification of traditional CV risk scores with, RRS underestimating and ASCVD overestimating the 10 year-coronary heart disease risk. A quarter of patients with ASCVD score 5-20% who were on statins had a CACS of 0; hence CACS can potentially help refine subjects who would best benefit from statin therapy.Fig 1Distribution of patients with %10-year risk based on MESA CAC score vs ASCVD (A) and RRS (B)

Introduction:Besides reporting conventional calcium score, coronary age was suggested as an original function of cardiovascular risk.Hypothesis:In a primary prevention cohort, we sought to assess the reclassification provided by coronary arterial age derived from the Multi-Ethnic Study of Atherosclerosis- coronary artery calcification 10-year risk score (MESA-CACS).Methods:Consecutive patients (n=5324 ,age 57± 8 years ,76% male and 87% white) undergoing CACS screening in a primary prevention clinic between 3/2016 and 10/2021 were retrospectively included in this study. Coronary arterial age was calculated for the patients using the formula provided by Blaha M et al 2021 by solving for age from MESA-CACS 10-year risk = 1–0.99963exp(0.04555*Age+2.45).Results:The distribution of the difference between the calculated coronary age and the chronological age is presented in Fig 1a, with 1823 (62%) patients with CAC of 0 being downgraded by >20 years and 298 (29%) of patients with CAC >75thpercentile being upgraded by >20 years. The average difference between coronary age and chronological age (years) across the CAC percentile groups is -23.7, -18.3, -7.4, -0.2 and +12.8 years for CAC of 0, 1-25, 26-50, 51-75 and >75thpercentile, respectively (Figure 1b).Conclusions:The use of coronary age is a simplified method of explaining the MESA-CAC cardiac risk status for the patients. In our study, coronary age was lower by more than 20 years versus chronological age for CAC percentiles between 0 and 50, almost equal with CAC percentile 51-75 and greater than chronological age by more than 10 years for CAC percentile >75.Fig 1A:Distribution of coronary age classification compared to the chronological across the CACS percentiles 1B:Mean difference between coronary and chronological age across the CACS percentile

Introduction:Apolipoprotein B (ApoB) and Lipoprotein a (Lpa) are emerging as important markers of coronary artery disease (CAD). In subjects without documented CAD, we assessed the association between ApoB and Lpa with coronary artery calcium scoring (CACS).Methods:We included 5324 subjects (age 57±8 years ,76% male & 87% white) referred for CACS in a primary prevention clinic between 3/2016 and 10/2021. 10-year multiethnic study on subclinical atherosclerosis CACS (MESA-CACS) risk score was calculated as 0, 1-4.99, 5-9.99 and >10%. ApoB (mg/dl) was divided into <104, 104-127 and >127, while Lpa (mg/dl) was divided into≤40 and >40. Additionally, Lpa was divided based on 60, 70 and 90 mg/dl cutoffs.Results:ApoB was significantly associated with MESA-CAC risk score (p<0.001); while Lpa had a borderline association (Table) (p=0.09). A significantly higher proportion of subjects with normal ApoB were in 0 MESA-CACS risk category (87%), with no difference in other risk categories (Figure 1A). Almost 25% patients with 0 MESA-CACS had Lpa of >40, with no significant difference between normal vs. elevated Lpa across MESA-CACS categories (Figure 1B). No significant difference was noted among the MESA-CACS categories with p-values of 0.284, 0.672 and 0.392 for Lpa cutoffs of 60, 70 and 90 mg/dl respectively. Despite a CACS of 0, 793 (15%) subjects had Lpa>40, while 690 (13%) had a CACS >75th percentile despite Lpa≤40.Conclusions:ApoB was significantly associated with MESA-CACS score, while Lpa only showed a weak association. Hence the addition of Lpa could add synergistic value to CACS in atherogenic risk. stratificationFig1Distribution of ApoB (A) and Lpa(B) across MESA-CACS groups

We present a description of our method to process a set of autocollimator-based deflectometer one-dimensional line scans taken over a large optical surface and reconstruct them to a best-fit conic-section surface. The challenge with our task is that each line scan is in a different (unknown) coordinate reference frame with respect to the other line scans in the set. This problem arises due to the limited angular measurement range of the autocollimator used in the deflectometer and the need to measure over a greater range. This results in the optic under measurement being rotated (in pitch and roll) between each scan to bring the autocollimator back into measurement range and therefore each scan is taken in a different coordinate frame. We describe an approach using a 6N+2 dimension optimization (where N is the number of scan lines taken across the mirror) that uses a gradient-based nonlinear least squares fitting combined with a multistart global-search strategy to find the best-fit surface. Careful formulation of the problem is required to reduce numerical noise and allow the routine to converge on a solution of the required accuracy.

Management of neoangiogenesis remains a high-value therapeutic goal. A recently uncovered association between the DNA damage repair pathway and pathological angiogenesis could open previously unexplored possibilities for intervention. An attractive and novel target is the Eyes absent (EYA) tyrosine phosphatase, which plays a critical role in the repair versus apoptosis decision after DNA damage. This study examines the role of EYA in the postnatal development of the retinal vasculature and under conditions of ischemia-reperfusion encountered in proliferative retinopathies. We find that the ability of the EYA proteins to promote endothelial cell (EC) migration contributes to a delay in postnatal development of the retinal vasculature when Eya3is deleted specifically in ECs. By using genetic and chemical biology tools, we show that EYA contributes to pathological angiogenesis in a model of oxygen-induced retinopathy. Both in vivoand in vitro, loss of EYA tyrosine phosphatase activity leads to defective assembly of γ-H2AX foci and thus to DNA damage repair in ECs under oxidative stress. These data reveal the potential utility of EYA tyrosine phosphatase inhibitors as therapeutic agents in inhibiting pathological neovascularization with a range of clinical applications.

Although the link between inflammation and cancer initiation is well established, its role in metastatic diseases, the primary cause of cancer deaths, has been poorly explored. Our previous studies identified a population of metastasis-associated macrophages (MAMs) recruited to the lung that promote tumor cell seeding and growth. Here we show that FMS-like tyrosine kinase 1 (Flt1, also known as VEGFR1) labels a subset of macrophages in human breast cancers that are significantly enriched in metastatic sites. In mouse models of breast cancer pulmonary metastasis, MAMs uniquely express FLT1. Using several genetic models, we show that macrophage FLT1 signaling is critical for metastasis. FLT1 inhibition does not affect MAM recruitment to metastatic lesions but regulates a set of inflammatory response genes, including colony-stimulating factor 1 (CSF1), a central regulator of macrophage biology. Using a gain-of-function approach, we show that CSF1-mediated autocrine signaling in MAMs is downstream of FLT1 and can restore the tumor-promoting activity of FLT1-inhibited MAMs. Thus, CSF1 is epistatic to FLT1, establishing a link between FLT1 and inflammatory responses within breast tumor metastases. Importantly, FLT1 inhibition reduces tumor metastatic efficiency even after initial seeding, suggesting that these pathways represent therapeutic targets in metastatic disease.

Activation of Wnt/β-catenin signaling during liver regeneration (LR) after partial hepatectomy (PH) is observed in several species. However, how this pathway is turned off when hepatocyte proliferation is no longer required is unknown. We assessed LR in liver-specific knockouts of Wntless (Wls-LKO), a protein required for Wnt secretion from a cell. When subjected to PH, Wls-LKO showed prolongation of hepatocyte proliferation for up to 4 days compared with littermate controls. This coincided with increased β-catenin–T-cell factor 4 interaction and cyclin-D1 expression. Wls-LKO showed decreased expression and secretion of inhibitory Wnt5a during LR. Wnt5a expression increased between 24 and 48 hours, and Frizzled-2 between 24 and 72 hours, after PH in normal mice. Treatment of primary mouse hepatocytes and liver tumor cells with Wnt5a led to a notable decrease in β-catenin–T-cell factor activity, cyclin-D1 expression, and cell proliferation. Intriguingly, Wnt5a-LKO did not display any prolongation of LR because of compensation by other cells. In addition, Wnt5a-LKO hepatocytes failed to respond to exogenous Wnt5a treatment in culture because of a compensatory decrease in Frizzled-2 expression. In conclusion, we demonstrate Wnt5a to be, by default, a negative regulator of β-catenin signaling and hepatocyte proliferation, both in vitroand in vivo. We also provide evidence that the Wnt5a/Frizzled-2 axis suppresses β-catenin signaling in hepatocytes in an autocrine manner, thereby contributing to timely conclusion of the LR process.

The belly spot and tail (Bst+/−) mouse phenotype is caused by mutations of the ribosomal protein L24 (Rpl24). Among various phenotypes in Bst+/− mice, the most interesting are its retinal abnormalities, consisting of delayed closure of choroid fissures, decreased ganglion cells and subretinal vascularization. We further characterized the Bst+/− mouse and investigated the underlying molecular mechanisms to assess the feasibility of using this strain as a model for stem cell therapy of retinal degenerative diseases due to retinal ganglion cell (RGC) loss. We found that, although RGCs are significantly reduced in retinal ganglion cell layer in Bst+/− mouse, melanopsin+ RGCs, also called ipRGCs, appear to be unchanged. Pupillary light reflex was completely absent in Bst+/− mice but they had a normal circadian rhythm. In order to examine the pathological abnormalities in Bst+/− mice, we performed electron microscopy in RGC and found that mitochondria morphology was deformed, having irregular borders and lacking cristae. The complex activities of the mitochondrial electron transport chain were significantly decreased. Finally, for subretinal vascularization, we also found that angiogenesis is delayed in Bst+/− associated with delayed hyaloid regression. Characterization of Bst+/− retina suggests that the Bst+/− mouse strain could be a useful murine model. It might be used to explore further the pathogenesis and strategy of treatment of retinal degenerative diseases by employing stem cell technology.

Wnt/β-catenin signaling is a central regulator of adult stem cells. Variable sensitivity of Wnt reporter transgenes, β-catenin’s dual roles in adhesion and signaling, and hair follicle degradation and inflammation resulting from broad deletion of epithelial β-catenin have precluded clear understanding of Wnt/β-catenin’s functions in adult skin stem cells. By inducibly deleting β-catenin globally in skin epithelia, only in hair follicle stem cells, or only in interfollicular epidermis and comparing the phenotypes with those caused by ectopic expression of the Wnt/β-catenin inhibitor Dkk1, we show that this pathway is necessary for hair follicle stem cell proliferation. However, β-catenin is not required within hair follicle stem cells for their maintenance, and follicles resume proliferating after ectopic Dkk1has been removed, indicating persistence of functional progenitors. We further unexpectedly discovered a broader role for Wnt/β-catenin signaling in contributing to progenitor cell proliferation in nonhairy epithelia and interfollicular epidermis under homeostatic, but not inflammatory, conditions.

Hematopoietic progenitor cells (HPCs) are central to hematopoiesis as they provide large numbers of lineage-defined blood cells necessary to sustain blood homeostasis. They are one of the most actively cycling somatic cells, and their precise control is critical for hematopoietic homeostasis. The small GTPase RhoA is an intracellular molecular switch that integrates cytokine, chemokine, and adhesion signals to coordinate multiple context-dependent cellular processes. By using a RhoA conditional knockout mouse model, we show that RhoA deficiency causes a multilineage hematopoietic failure that is associated with defective multipotent HPCs. Interestingly, RhoA−/− hematopoietic stem cells retained long-term engraftment potential but failed to produce multipotent HPCs and lineage-defined blood cells. This multilineage hematopoietic failure was rescued by reconstituting wild-type RhoA into the RhoA−/− Lin−Sca-1+c-Kit+ compartment. Mechanistically, RhoA regulates actomyosin signaling, cytokinesis, and programmed necrosis of the HPCs, and loss of RhoA results in a cytokinesis failure of HPCs manifested by an accumulation of multinucleated cells caused by failed abscission of the cleavage furrow after telophase. Concomitantly, the HPCs show a drastically increased death associated with increased TNF–RIP-mediated necrosis. These results show that RhoA is a critical and specific regulator of multipotent HPCs during cytokinesis and thus essential for multilineage hematopoiesis.

The treatment of festering wounds is one of the most important aspects of medical care. Macrophages are important components of wound repair, both in fending off infection and in coordinating tissue repair. Here we show that macrophages use a Wnt-Calcineurin-Flt1 signaling pathway to suppress wound vasculature and delay repair. Conditional mutants deficient in both Wntless/GPR177, the secretory transporter of Wnt ligands, and CNB1, the essential component of the nuclear factor of activated T cells dephosporylation complex, displayed enhanced angiogenesis and accelerated repair. Furthermore, in myeloid-like cells, we show that noncanonical Wnt activates Flt1, a naturally occurring inhibitor of vascular endothelial growth factor-A–mediated angiogenesis, but only when calcineurin function is intact. Then, as expected, conditional deletion of Flt1 in macrophages resulted in enhanced wound angiogenesis and repair. These results are consistent with the published link between enhanced angiogenesis and enhanced repair, and establish novel therapeutic approaches for treatment of wounds.

The treatment of festering wounds is one of the most important aspects of medical care. Macrophages are important components of wound repair, both in fending off infection and in coordinating tissue repair. Here we show that macrophages use a Wnt-Calcineurin-Flt1 signaling pathway to suppress wound vasculature and delay repair. Conditional mutants deficient in both Wntless/GPR177, the secretory transporter of Wnt ligands, and CNB1, the essential component of the nuclear factor of activated T cells dephosporylation complex, displayed enhanced angiogenesis and accelerated repair. Furthermore, in myeloid-like cells, we show that noncanonical Wnt activates Flt1, a naturally occurring inhibitor of vascular endothelial growth factor-A–mediated angiogenesis, but only when calcineurin function is intact. Then, as expected, conditional deletion of Flt1 in macrophages resulted in enhanced wound angiogenesis and repair. These results are consistent with the published link between enhanced angiogenesis and enhanced repair, and establish novel therapeutic approaches for treatment of wounds.

For ease of reading, certain cases have been omitted from this summary. They are cases solely concerning the length of proceedings, cases solely concerning the presence of a military judge on the bench, cases solely concerning the censorship of letters, and other “repetitive” or “recurrent” cases which disclose no new point of law.

For ease of reading, certain cases have been omitted from this summary. They are cases solely concerning the length of proceedings, cases solely concerning the presence of a military judge on the bench, cases solely concerning the censorship of letters, and other ‘repetitive’ or ‘recurrent’ cases which disclose no new point of law.

Background and Objective:To determine the accuracy and sensitivity of a single-field non-mydriatic digital fundus image interpreted by an ophthalmologist and performed within a primary care setting.Patients and Methods:Fundus photography using a digital non-mydriatic camera was performed on both eyes of 1,175 consecutive patients as part of an executive health program. All fundus images included a 45° field of the posterior pole capturing the optic nerve and macular area. Diagnostic findings were recorded and appropriate recommendations for follow-up were made. Patients were then contacted to see whether appropriate follow-up was successfully completed and chart reviews were performed to determine biomicroscopic findings.Results:Photographs were adequate in both eyes in 1,117 patients (95.1%). Examination findings were normal in both eyes in 951 (85.1%) patients. Abnormal findings were noted in either eye in 166 (14.9%) patients. The most common abnormal findings were macular degeneration (57/166, 34.3%), optic nerve cupping (45/166, 27.1%), hypertensive retinopathy (15/166, 9.0%), and choroidal nevi (10/166, 6.0%). In all patients with abnormal findings, routine follow-up ophthalmologic examination with an eye care specialist was indicated and none of the patients required urgent attention. Sensitivity was found to be 87% and stratification was performed based on the initial diagnosis. False-positive results were from confounding diagnoses rather than true false-positives.Conclusion:Single-field non-mydriatic fundus photography is accurate and sensitive for screening retinal disease in a primary care setting.