Inherited Retinal Degeneration Caused by Dehydrodolichyl Diphosphate Synthase Mutation-Effect of an ALG6 Modifier Variant.

Modern advances in disease genetics have uncovered numerous modifier genes that play a role in the severity of disease expression. One such class of genetic conditions is known as inherited retinal degenerations (IRDs), a collection of retinal degenerative disorders caused by mutations in over 300 genes. A single missense mutation (K42E) in the gene encoding the enzyme dehydrodolichyl diphosphate synthase (DHDDS), which is required for protein N-glycosylation in all cells and tissues, causes DHDDS-IRD (retinitis pigmentosa type 59 (RP59; OMIM #613861)). Apart from a retinal phenotype, however, DHDDS-IRD is surprisingly non-syndromic (i.e., without any systemic manifestations). To explore disease pathology, we selected five glycosylation-related genes for analysis that are suggested to have disease modifier variants. These genes encode glycosyltransferases (ALG6, ALG8), an ER resident protein (DDOST), a high-mannose oligosaccharyl transferase (MPDU1), and a protein N-glycosylation regulatory protein (TNKS). DNA samples from 11 confirmed DHDDS (K42E)-IRD patients were sequenced at the site of each candidate genetic modifier. Quantitative measures of retinal structure and function were performed across five decades of life by evaluating foveal photoreceptor thickness, visual acuity, foveal sensitivity, macular and extramacular rod sensitivity, and kinetic visual field extent. The ALG6 variant, (F304S), was correlated with greater macular cone disease severity and less peripheral rod disease severity. Thus, modifier gene polymorphisms may account for a significant portion of phenotypic variation observed in human genetic disease. However, the consequences of the polymorphisms may be counterintuitively complex in terms of rod and cone populations affected in different regions of the retina.

Cetuximab and anemia prevention in head and neck cancer patients undergoing radiotherapy.

BACKGROUND: Epidermal growth factor receptor (EGFR) activation is associated with increased production of interleukin 6 (IL6), which is intensified by radiotherapy (RT) induced inflammatory response. Elevated IL6 levels intensifies RT-induced anemia by upregulating hepcidin causing functional iron deficiency. Cetuximab, an EGFR inhibitor, has been associated with lower rates of anemia for locally advanced head and neck squamous cell carcinoma (HNSCC). We hypothesized that concomitant cetuximab could prevent RT-induced anemia. METHODS: We queried our institutional head and neck cancers database for non-metastatic HNSCC cases that received RT with concomitant cetuximab or RT-only between 2006 and 2018. Cetuximab was administered for some high-risk cases medically unfit for platinum agents per multidisciplinary team evaluation. We only included patients who had at least one complete blood count in the 4 months preceding and after RT. We compared the prevalence of anemia (defined as hemoglobin (Hb) below 12 g/dL in females and 13 g/dL in males) and mean Hb levels at baseline and after RT. Improvement of anemia/Hb (resolution of baseline anemia and/or an increase of baseline Hb ≥1 g/dL after RT), and overall survival (OS) in relation to anemia/Hb dynamics were also compared. RESULTS: A total of 171 patients were identified equally distributed between cetuximab-plus-RT and RT-only groups. The cetuximab-plus-RT group had more locally-advanced stage, oropharyngeal and high grade tumors (p < 0.001 for all). Baseline anemia/Hb were similar, however anemia after RT conclusion was higher in the cetuximab-plus-RT vs RT-only (63.5% vs. 44.2%; p = 0.017), with a mean Hb of 11.98 g/dL vs. 12.9 g/dL; p = 0.003, for both respectively. This contributed to significantly worse anemia/Hb improvement for cetuximab-plus-RT (18.8% vs. 37.2%; p = 0.007). This effect was maintained after adjusting for other factors in multivariate analysis. The prevalence of iron, vitamin-B12 and folate deficiencies; and chronic kidney disease, was non-different. Baseline anemia was associated with worse OS (p = 0.0052) for the whole study cohort. Nevertheless, improvement of anemia/Hb was only marginally associated with better OS (p = 0.068). CONCLUSIONS: In contrast to previous studies, cetuximab was not associated with lower rates of anemia after RT for nonmetastatic HNSCC patients compared to RT-alone. Dedicated prospective studies are needed to elucidate the effect of cetuximab on RT-induced anemia.

Mobility test to assess functional vision in dark-adapted patients with Leber congenital amaurosis.

BACKGROUND: Inherited retinal degenerations (IRDs) affect daylight and night vision to different degrees. In the current work, we devise a method to quantify mobility under dark-adapted conditions in patients with severe childhood blindness due to Leber congenital amaurosis (LCA). Mobility thresholds from two different LCA genotypes are compared to dark-adapted vision measurements using the full-field stimulus test (FST), a conventional desktop outcome measure of rod vision. METHODS: A device consisting of vertical LED strips on a plane resembling a beaded curtain was programmed to produce a rectangular pattern target defining a 'door' of varying luminance that could appear at one of three positions. Mobility performance was evaluated by letting the subject walk from a fixed starting position ~ 4 m away from the device with instructions to touch the door. Success was defined as the subject touching within the 'door' area. Ten runs were performed and the process was repeated for different levels of luminance. Tests were performed monocularly in dark-adapted and dilated eyes. Results from LCA patients with the GUCY2D and CEP290 genotypes and normal subjects were analyzed using logistic regression to estimate the mobility threshold for successful navigation. The relation of thresholds for mobility, FST and visual acuity were quantified using linear regression. RESULTS: Normal subjects had mobility thresholds near limits of dark-adapted rod vision. GUCY2D-LCA patients had a wide range of mobility thresholds from within 1 log of normal to greater than 8 log abnormal. CEP290-LCA patients had abnormal mobility thresholds that were between 5 and 6 log from normal. Sensitivity loss estimates using FST related linearly to the mobility thresholds which were not correlated with visual acuity. CONCLUSIONS: The mobility task we developed can quantify functional vision in severely disabled patients with LCA. Taken together with other outcome measures of rod and cone photoreceptor-mediated vision, dark-adapted functional vision should provide a more complete understanding of the natural history and effects of treatment in patients with LCA.

Leber Congenital Amaurosis Due to GUCY2D Mutations: Longitudinal Analysis of Retinal Structure and Visual Function.

Gene augmentation therapy is being planned for GUCY2D-associated Leber congenital amaurosis (LCA). To increase our understanding of the natural history of GUCY2D-LCA, patients were evaluated twice with an interval of 4 to 7 years between visits using safety and efficacy outcome measures previously determined to be useful for monitoring this disorder. In this group of molecularly-identified LCA patients (n = 10; ages 7-37 years at first visit), optical coherence tomography (OCT) was used to measure foveal cone outer nuclear layer (ONL) thickness and rod ONL at a superior retinal locus. Full-field stimulus testing (FST) with chromatic stimuli in dark- and light-adapted states was used to assay rod and cone vision. Changes in OCT and FST over the interval were mostly attributable to inter-visit variability. There were no major negative changes in structure or function across the cohort and over the intervals studied. Variation in severity of disease expression between patients occurs; however, despite difficulties in quantifying structure and function in such seriously visually impaired individuals with nystagmus, the present work supports the use of OCT as a safety outcome and FST as an efficacy outcome in a clinical trial of GUCY2D-LCA. A wide age spectrum for therapy was confirmed, and there was relative stability of structure and function during a typical time interval for clinical trials.

Food safety lessons learned from the COVID-19 pandemic.

The COVID-19 pandemic has ushered in a new era of food safety. To date, there is no evidence to suggest that consuming food is associated with COVID-19. Nevertheless, COVID-19's impact on food safety and security has been grave. The world is currently experiencing several supply chain issues as a direct result of extensive lockdowns and impacts on essential workers' safety. However, disruption in the food supply, while catastrophic in nature, has created opportunities for the advancement of medical science, data processing, security monitoring, foodborne pathogen detection, and food safety technology. This article will discuss the key components for food safety during the COVID-19 pandemic. The discussion will draw from lessons learned early in the outbreak and will analyze the etiology of the disease through a food safety perspective. From there, we will discuss personal protective equipment, detection of SARS-CoV-2, useful surrogates to study SARS-CoV-2, and the expanding field of data science, from the food safety point of view. In the future, scientists can apply the knowledge to the containment of COVID-19 and eventually to future pandemics.

A review of epidemic investigation on cold-chain food-mediated SARS-CoV-2 transmission and food safety consideration during COVID-19 pandemic.

COVID-19 has brought speculations on potential transmission routes of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of the pandemic. It is reported that the main route of virus transmission to be person-to-person by respiratory droplets; however, people have raised concerns on the possible transmission of SARS-CoV-2 to humans via food and packaging and its potential effects on food safety. This review discusses food safety issues in the COVID-19 pandemic and reveals its possible transmission in cold-chain food. The first outbreak of COVID-19 in late 2019 was associated with a seafood market in Wuhan, China, while the second outbreak of COVID-19 in June 2020 was also related to a seafood market in Beijing, China. As of 2020, several frozen seafood products linked with SARS-CoV-2 have been reported in China. According to the current survey and scientific studies, the risk of infection by SARS-CoV-2 from cold-chain food, food products, and food packaging is thought to be very low. However, studies on food cold chain contamination have shown that SARS-CoV-2 remained highly stable under refrigerated (4°C) and even in freezing conditions (-10 to -80°C). Since one mode of SARS-CoV-2 transmission appears to be touching contaminated surfaces, it is important to clean and sanitize food contact surfaces properly. Understanding food safety hazard risks is essential to avoid potential negative health effects and SARS-CoV-2 transmission in the food supply chain during the COVID-19 pandemic.

Effects of lyophilization on the stability of bacteriophages against different serogroups of Shiga toxin-producing Escherichia coli.

Lyophilization is commonly used to effectively preserve the stability of bacteriophages (phages) in long-term storage. However, information regarding the lyophilization of phages specific to Shiga toxin-producing Escherichia coli (STEC) strains is scarce. The objective of this study was to determine the effects of lyophilization with different cryoprotectants (sucrose and trehalose) and concentrations (0.1 M and 0.5 M) on the stability of seven lytic phages specific to STEC O157 and top 6 non-O157 strains during 6-month storage at -80 °C. The titers of lyophilized phages specific to STEC O26 (S1 O26) and STEC O121 (Pr121lvw) did not exhibit significant reduction after 6-month storage regardless of the use of cryoprotectants. Phages lytic against STEC O103 (Ro103C3lw) and STEC O145 (Ro145clw) with 0.1 M sucrose retained similar titers after lyophilization and frozen storage for 6 months (P > 0.05). Despite subtle differences, these results indicated that most of the selected phages had similar titer retention with the same cryoprotectants. Additionally, lytic activities of the phages against their primary hosts were not affected after lyophilization and 6-month frozen storage. Moreover, no detectable damage was observed on the lyophilized phage structures. These findings provide valuable insight into the use of lyophilization to preserve phages lytic against STEC strains.

Gaseous antimicrobial treatments to control foodborne pathogens on almond kernels and whole black peppercorns.

Gaseous treatments with ClO2 and O3 on low-moisture foods (LMFs) have been reported for their efficient bacterial reduction without affecting the external quality of food. However, these studies were conducted on a small scale, which limits their application to LMF industries. We aimed to evaluate the effectiveness of gaseous antimicrobial intervention with ClO2 or O3 to reduce foodborne pathogens (Shiga toxin-producing Escherichia coli, serovars of Salmonella enterica, and Listeria monocytogenes) inoculated on almonds and peppercorns maintained under various conditions. Almonds were treated for over 4 or 6 h. Peppercorns were treated for over 2.5 or 4 h. Gaseous O3 treatment was used for 6 h on almonds and 2 or 4 h on peppercorns. Additionally, the effects of relative humidity (RH) during the treatment of peppercorns and post-treatment heating on almonds were evaluated. Heating at 65 °C post-ClO2 treatment yielded the highest bacterial log reduction of 4.6 CFU/g on almonds, while 80% RH resulted in 3.7-log bacterial reduction on peppercorns. Gaseous O3 resulted in maximum log reductions of 1.3 and 2.5 CFU/g on almonds and peppercorns, respectively. No visual damage was observed. In conclusion, ClO2 was more efficient than O3 and the treatment can be incorporated into industrial practices.

Autosomal Dominant Retinitis Pigmentosa Due to Class B Rhodopsin Mutations: An Objective Outcome for Future Treatment Trials.

Gene therapy for adRP due to RHO mutations was recently shown to prevent photoreceptor death in a canine model of Class B disease. Among translational steps to be taken, one is to determine a method to detect efficacy in a human clinical trial. The relatively slow progression of adRP becomes a difficulty for clinical trials requiring an answer to whether there is slowed progression of degeneration in response to therapy. We performed a single-center, retrospective observational study of cross-sectional and longitudinal data. The study was prompted by our identification of a pericentral disease distribution in Class B RHO-adRP. Ultrawide optical coherence tomography (OCT) scans were used. Inferior retinal pericentral defects was an early disease feature. Degeneration further inferior in the retina merged with the pericentral defect, which extended into superior retina. In about 70% of patients, there was an asymmetric island of structure with significantly greater superior than inferior ellipsoid zone (EZ) extent. Serial measures of photoreceptor structure by OCT indicated constriction in superior retinal extent within a two-year interval. We conclude that these results should allow early-phase trials of therapy in RHO-adRP to move forward by inclusion of patients with an asymmetric extent of photoreceptor structure and by monitoring therapeutic effects over two years in the superior retina, a reasonable target for subretinal injection.

Group 5 ITI Consensus Report: Digital technologies.

OBJECTIVES: Working Group 5 was assigned the task to review the current knowledge in the area of digital technologies. Focused questions on accuracy of linear measurements when using CBCT, digital vs. conventional implant planning, using digital vs. conventional impressions and assessing the accuracy of static computer-aided implant surgery (s-CAIS) and patient-related outcome measurements when using s-CAIS were addressed. MATERIALS AND METHODS: The literature was systematically searched, and in total, 232 articles were selected and critically reviewed following PRISMA guidelines. Four systematic reviews were produced in the four subject areas and amply discussed in the group. After emendation, they were presented to the plenary where after further modification, they were accepted. RESULTS: Static computer-aided surgery (s-CAIS), in terms of pain & discomfort, economics and intraoperative complications, is beneficial compared with conventional implant surgery. When using s-CAIS in partially edentulous cases, a higher level of accuracy can be achieved when compared to fully edentulous cases. When using an intraoral scanner in edentulous cases, the results are dependent on the protocol that has been followed. The accuracy of measurements on CBCT scans is software dependent. CONCLUSIONS: Because the precision intraoral scans and of measurements on CBCT scans and is not high enough to allow for the required accuracy, s-CAIS should be considered as an additional tool for comprehensive diagnosis, treatment planning, and surgical procedures. Flapless s-CAIS can lead to implant placement outside of the zone of keratinized mucosa and thus must be executed with utmost care.

Effectiveness of different antimicrobial washes combined with freezing against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes inoculated on blueberries.

To ensure the safety of produce, including blueberries, elimination of potential pathogens is critical. This study evaluated the efficacy of antimicrobial washes when coupled with frozen storage against Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes on wild blueberries. Inoculated blueberries were sprayed with antimicrobial solutions at different concentrations for various contact times (chlorine dioxide -2.5, 5, 10, and 15 ppm for 10 s, 1, 5, and 10 min; chlorine -100, 150, and 200 ppm for 10s, 1, 5, and 10 min; lactic acid 1 and 2% for 5, 10 and 20 min) and following treatment, stored at -12 °C for 1 week. Compared to antimicrobial washing alone, the additional freezing significantly reduced pathogens (P < 0.05). Concentrations of all three antimicrobials combined with freezing reduced L. monocytogenes to undetectable levels (detection limit < 1 log CFU/g). The greatest reduction of E. coli O157:H7 (4.4 log CFU/g) and Salmonella (5.4 log CFU/g) was achieved by 2% lactic acid or 200 ppm Cl2 followed with frozen storage. These antimicrobials maintained the visual quality of blueberries and did not leave detectable residues. In conclusion, antimicrobial washes, when combined with frozen storage, effectively reduce the risk of pathogen contamination on blueberries.

Preparation of Fish Skin Gelatin-Based Nanofibers Incorporating Cinnamaldehyde by Solution Blow Spinning.

Cinnamaldehyde, a natural preservative that can non-specifically deactivate foodborne pathogens, was successfully incorporated into fish skin gelatin (FSG) solutions and blow spun into uniform nanofibers. The effects of cinnamaldehyde ratios (5-30%, w/w FSG) on physicochemical properties of fiber-forming emulsions (FFEs) and their nanofibers were investigated. Higher ratios resulted in higher values in particle size and viscosity of FFEs, as well as higher values in diameter of nanofibers. Loss of cinnamaldehyde was observed during solution blow spinning (SBS) process and cinnamaldehyde was mainly located on the surface of resultant nanofibers. Nanofibers all showed antibacterial activity by direct diffusion and vapor release against Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes. Inhibition zones increased as cinnamaldehyde ratio increased. Nanofibers showed larger inhibition effects than films prepared by casting method when S. typhimurium was exposed to the released cinnamaldehyde vapor, although films had higher remaining cinnamaldehyde than nanofibers after preparation. Lower temperature was favorable for cinnamaldehyde retention, and nanofibers added with 10% cinnamaldehyde ratio showed the highest retention over eight-weeks of storage. Results suggest that FSG nanofibers can be prepared by SBS as carriers for antimicrobials.

Comparison of Long-run Trends in 30-day Readmission by Degrees of Medicare Payment Cuts.

BACKGROUND AND OBJECTIVE: The Affordable Care Act enacted significant Medicare payment reductions to providers, yet long-term effects of such major reductions on patient outcomes remain uncertain. Using the 1997 Balanced Budget Act (BBA) as an experiment, we compare long-run trends in 30-day readmission across hospitals with different amount of payment cuts. RESEARCH DESIGN, SUBJECTS, AND MEASURES: Using 100% Medicare claims between 1995 and 2011 and instrumental variable hospital fixed-effects regression models, we compared changes in 30-day readmission trends for 5 leading Medicare conditions between urban hospitals facing small, moderate, and large BBA payment reductions across 4 periods [1995-1997 (pre-BBA period), 1998-2000, 2001-2005, 2006-2001]. Patient sample includes Medicare patients who were admitted to general, acute, urban, short-stay hospitals in the United States 1995-2011. Sample size ranges from 1.4 million patients for acute myocardial infarction to 3 million for pneumonia. RESULTS: We found that 30-day readmission trends diverged post-BBA (2001-2005) between hospitals facing small and large payment cuts, where large-cut hospitals experience slower improvement in readmission rates relative to small-cut hospitals. The gap between small-cut and large-cut hospitals readmission trend was 6% for acute myocardial infarction, 4% for congestive heart failure and pneumonia (all P<0.01) in the 2001-2005 period. The gaps between hospitals were eliminated by the 2006-2011 period as the effect of BBA naturally dissipated over time. CONCLUSIONS: Although payment-cut differences are associated with widening gaps in readmission rates across hospitals, the negative association appears to dissipate in the long run.

Differential developmental trajectories of magnetic susceptibility in human brain gray and white matter over the lifespan.

As indicated by several recent studies, magnetic susceptibility of the brain is influenced mainly by myelin in the white matter and by iron deposits in the deep nuclei. Myelination and iron deposition in the brain evolve both spatially and temporally. This evolution reflects an important characteristic of normal brain development and ageing. In this study, we assessed the changes of regional susceptibility in the human brain in vivo by examining the developmental and ageing process from 1 to 83 years of age. The evolution of magnetic susceptibility over this lifespan was found to display differential trajectories between the gray and the white matter. In both cortical and subcortical white matter, an initial decrease followed by a subsequent increase in magnetic susceptibility was observed, which could be fitted by a Poisson curve. In the gray matter, including the cortical gray matter and the iron-rich deep nuclei, magnetic susceptibility displayed a monotonic increase that can be described by an exponential growth. The rate of change varied according to functional and anatomical regions of the brain. For the brain nuclei, the age-related changes of susceptibility were in good agreement with the findings from R2* measurement. Our results suggest that magnetic susceptibility may provide valuable information regarding the spatial and temporal patterns of brain myelination and iron deposition during brain maturation and ageing.

Decomposition of the drivers of the U.S. hospital spending growth, 2001-2009.

BACKGROUND: United States health care spending rose rapidly in the 2000s, after a period of temporary slowdown in the 1990s. However, the description of the overall trend and the understanding of the underlying drivers of this trend are very limited. This study investigates how well historical hospital cost/revenue drivers explain the recent hospital spending trend in the 2000s, and how important each of these drivers is. METHODS: We used aggregated time series data to describe the trend in total hospital spending, price, and quantity between 2001 and 2009. We used the Oaxaca-Blinder method to investigate the relative importance of major hospital cost/spending drivers (derived from the literature) in explaining the change in hospital spending patterns between 2001 and 2007. We assembled data from Medicare Cost Reports, American Hospital Association annual surveys, Prospective Payment System (PPS) Impact Files, Medicare Provider Analysis and Review (MedPAR) Medicare claims data, InterStudy reports, National Health Expenditure data, and Area Resource Files. RESULTS: Aggregated time series trends show that high hospital spending between 2001 and 2009 appears to be driven by higher payment per unit of hospital output, not by increased utilization. Results using the Oaxaca-Blinder regression decomposition method indicate that changes in historically important spending drivers explain a limited 30% of unit-payment growth, but a higher 60% of utilization growth. Hospital staffing and labor-related costs, casemix, and demographics are the most important drivers of higher hospital revenue, utilization, and unit-payment. Technology is associated with lower utilization, higher unit payment, and limited increases in total revenue. Market competition, primarily because of increased managed care concentration, moderates total revenue growth by driving lower unit payment. CONCLUSIONS: Much of the rapidly rising hospital spending growth in the 2000s in the United States is driven by factors not commonly known or well measured. Future studies need to explore new factors and dynamics that drive longer-term hospital spending growth in recent years, particularly through the channel of higher prices.

Adamantinoma-Like Ewing Sarcoma Mimicking Merkel Cell Carcinoma in the Parotid Gland: A Diagnostic Pitfall.

Adamantinoma-like Ewing sarcoma (ALES) is a newly described rare entity, which shows EWSR1::FLI1 rearrangement characteristic of Ewing sarcoma. This can be diagnostically challenging as it manifests histologically with epithelial differentiation and has diffuse keratin expression as well as p40 and p60 positivity. We hereby report a case of ALES in a 33-year-old woman with a past medical history of breast carcinoma who presented with a right-sided parotid mass. CT scan of the neck showed a heterogenous mass within the superficial lobe, measuring 17 mm in diameter for which the patient underwent superficial parotidectomy. Histopathology of the mass revealed a malignant neoplasm formed of solid nests, cords and sheets of cells with minimal cytoplasm and monomorphic nuclei with granular chromatin and indistinct nucleoli. Brisk mitotic activity and tumor necrosis were also present. The tumor showed strong and diffuse reactivity for pankeratin (clone AE1/AE3) and keratin 20, both in a dot-like pattern, raising the suspicion of metastatic Merkel cell carcinoma; however, molecular studies showed EWSR1::FLI1 rearrangement, supporting the diagnosis of ALES. In summary, it is prudent to have knowledge about this entity to avoid its misdiagnosis as other malignancies of the head and neck region which exhibit a different clinical course, prognosis and hence treatment modalities.

Benefits of isochoric freezing for carrot juice preservation.

Isochoric freezing (IF) at -5°C/77 and -10°C/100 MPa was used to preserve carrot juice for 12 weeks. The juice qualities were compared to those using heat treatment (HT) at 95°C for 15 s followed by cold storage at 4°C. The native population of total aerobic bacteria, yeasts, and molds in isochoric frozen juice remained below the detection limit for 12 weeks. In comparison, microbes started to grow in heat-treated juices after 3 weeks of refrigeration. The color of isochoric frozen juice appeared more deep orange than the fresh juice due to an increase in carotenoid extractability. IF was not effective in reducing the activities of peroxidase, polyphenol oxidase, and pectin methyl esterase compared with HT. However, the isochoric samples showed higher carotenoid content, polyphenol content, and antioxidant capacity compared to the fresh and heat-treated juices. PRACTICAL APPLICATION: Isochoric freezing was used to produce carrot juice with extended shelf life. Isochoric freezing could be a beneficial alternative to conventional heat treatment for carrot juice processing as the applied pressures reached total inactivation levels of spoilage microorganisms. Moreover, the low processing temperatures better retained desirable compounds and quality attributes of fresh juice throughout its shelf life.

Characterization of two novel Salmonella phages having biocontrol potential against Salmonella spp. in gastrointestinal conditions.

Salmonella is a primary enteric pathogen related to the contamination of poultry and other food products in numerous foodborne outbreaks. The continuous emergence of multidrug-resistant bacteria has become a serious issue due to the overuse of antibiotics. Hence, lytic phages are considered alternative biocontrol agents against these bacterial superbugs. Here, two Salmonella phages-S4lw and D5lw-were subjected to genomic and biological characterization and further encapsulated to improve the stability under acidic conditions mimicking gastrointestinal conditions. The two lytic phages, S4lw and D5lw, taxonomically belong to new species under the Guernseyvirinae and Ackermannviridae families, respectively. Each phage showed antimicrobial activities against diverse Salmonella spp., such as S. Enteritidis and S. Typhimurium, achieving 1.7-3.4 log reduction after 2-6 h of treatment. The phage cocktail at a multiplicity of infection (MOI) of 100 or 1000 completely inhibited these Salmonella strains for at least 14 h at 25 °C. Additionally, the bead-encapsulated phage cocktail could withstand low pH and different simulated gut environments for at least 1 h. Overall, the newly isolated phages can potentially mitigate Salmonella spp. under the gastrointestinal environments through encapsulation and may be further applied via oral administration to resolve common antimicrobial resistance issues in the poultry production chain.

Role of Argininosuccinate Synthase 1 -Dependent L-Arginine Biosynthesis in the Protective Effect of Endothelial Sirtuin 3 Against Atherosclerosis.

Atherosclerosis is initiated with endothelial cell (EC) dysfunction and vascular inflammation under hyperlipidemia. Sirtuin 3 (SIRT3) is a mitochondrial deacetylase. However, the specific role of endothelial SIRT3 during atherosclerosis remains poorly understood. The present study aims to study the role and mechanism of SIRT3 in EC function during atherosclerosis. Wild-type Sirt3f/f mice and endothelium-selective SIRT3 knockout Sirt3f/f; Cdh5Cre/+ (Sirt3EC-KO) mice are injected with adeno-associated virus (AAV) to overexpress PCSK9 and fed with high-cholesterol diet (HCD) for 12 weeks to induce atherosclerosis. Sirt3EC-KO mice exhibit increased atherosclerotic plaque formation, along with elevated macrophage infiltration, vascular inflammation, and reduced circulating L-arginine levels. In human ECs, SIRT3 inhibition resulted in heightened vascular inflammation, reduced nitric oxide (NO) production, increased reactive oxygen species (ROS), and diminished L-arginine levels. Silencing of SIRT3 results in hyperacetylation and deactivation of Argininosuccinate Synthase 1 (ASS1), a rate-limiting enzyme involved in L-arginine biosynthesis, and this effect is abolished in mutant ASS1. Furthermore, L-arginine supplementation attenuates enhanced plaque formation and vascular inflammation in Sirt3EC-KO mice. This study provides compelling evidence supporting the protective role of endothelial SIRT3 in atherosclerosis and also suggests a critical role of SIRT3-induced deacetylation of ASS1 by ECs for arginine synthesis.

Retinal response to light exposure in BEST1-mutant dogs evaluated with ultra-high resolution OCT.

Mutations in BEST1 cause an autosomal recessive disease in dogs where the earliest changes localize to the photoreceptor-RPE interface and show a retina-wide micro-detachment that is modulated by light exposure. The purpose of this study was to define the spatial and temporal details of the outer retina and its response to light with ultra-high resolution OCT across a range of ages and with different BEST1 mutations. Three retinal regions were selected in each eye: near the fovea-like area, near the optic nerve, both in the tapetal area, and inferior to the optic nerve in the non-tapetal area. The OS+ slab thickness was defined between the peak near the junction of inner and outer segments (IS/OS) and the transition between basal RPE, Bruch membrane, choriocapillaris and proximal tapetum (RPE/T). In wildtype (WT) dogs, two tapetal regions showed additional hyperscattering OCT peaks within the OS+ slab likely representing cone and rod outer segment tips (COST and ROST). The inferior non-tapetal region of WT dogs had only one of these peaks, likely ROST. In dogs with BEST1 mutations, all three locations showed a single peak, likely suggesting optical silence of COST. Light-dependent expansion of the micro-detachment by about 10 um was detectable in both tapetal and non-tapetal retina across all ages and BEST1 mutations.