Distinct dynamics of mRNA LNPs in mice and nonhuman primates revealed by in vivo imaging.

The characterization of vaccine distribution to relevant tissues after in vivo administration is critical to understanding their mechanisms of action. Vaccines based on mRNA lipid nanoparticles (LNPs) are now being widely considered against infectious diseases and cancer. Here, we used in vivo imaging approaches to compare the trafficking of two LNP formulations encapsulating mRNA following intramuscular administration: DLin-MC3-DMA (MC3) and the recently developed DOG-IM4. The mRNA formulated in DOG-IM4 LNPs persisted at the injection site, whereas mRNA formulated in MC3 LNPs rapidly migrated to the draining lymph nodes. Furthermore, MC3 LNPs induced the fastest increase in blood neutrophil counts after injection and greater inflammation, as shown by IL-1RA, IL-15, CCL-1, and IL-6 concentrations in nonhuman primate sera. These observations highlight the influence of the nature of the LNP on mRNA vaccine distribution and early immune responses.

Effect of Sleep-Related Symptoms on Recovery From a Sport-Related Concussion.

Background: Sleep issues are commonly reported in athletes after a sport-related concussion (SRC). Further studies are needed to evaluate screening methods for sleep disturbances and the risk of persisting symptoms after an SRC. Purpose: To evaluate the association between the Sport Concussion Assessment Tool 5 (SCAT5) symptoms of trouble falling asleep, fatigue (or low energy), and drowsiness and the risk of persisting symptoms (≥28 days to recovery) in adolescent athletes. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 519 athletes aged 13 to 18 years reported any sleep-related symptoms with an SRC, scored as none (0), mild (1-2), moderate (3-4), or severe (5-6), at their initial office visit (median, 5.4 days after an SRC). Scores were correlated with the risk of persisting symptoms. A composite "sleep cluster" score (range, 0-18) was calculated by summing the SCAT5 component items for trouble falling asleep, fatigue, and drowsiness. Results: The results indicated that, compared with athletes who reported that they did not have each symptom, (1) athletes who reported mild, moderate, or severe trouble falling asleep were 3.0, 4.6, and 6.7 times more likely to have persisting symptoms, respectively; (2) athletes reporting mild, moderate, or severe fatigue (or low energy) were 2.6, 4.8, and 7.6 times more likely to have persisting symptoms, respectively; and (3) athletes reporting mild, moderate, or severe drowsiness were 1.9, 4.6, and 6.8 times more likely to have persisting symptoms, respectively (P < .001 for all). For every 1-point increase in the sleep cluster score, there was a 1.2-fold increased risk of persisting symptoms and an additional 2.4 days of recovery required (P < .001 for both). Conclusion: Athletes who reported mild, moderate, or severe sleep-related symptoms on the SCAT5 were at a proportionally increased risk of persisting symptoms at the initial office visit.

Bronchoalveolar Lavage Fluid Cytology in Healthy Cynomolgus Macaques.

Bronchoalveolar lavage, or BAL, is a minimally invasive procedure frequently used for clinical and non-clinical research, allowing studies of the respiratory system. Macaques are the most widely used non-human primate models in biomedical research. However, very little information is available in the literature concerning BAL cytology in macaques. The purpose of this study was to establish BAL reference values and document an atlas of BAL cytology from healthy cynomolgus macaques. BALs were obtained from 30 macaques and BAL fluid differential cell counts based on 400 nucleated cells/BAL sample were performed by a board-certified clinical pathologist. Results were analyzed using Reference Value Advisor macroinstructions and the effect of blood and oropharyngeal contaminations was investigated. Overall, nucleated cells interval percentages in BAL fluids were 55.8 to 93.7 for macrophages, 1.8 to 37.1 for lymphocytes, 0.4 to 8.7 for neutrophils, and 0.4 to 9.8 for eosinophils. Mild oropharyngeal contamination did not affect BAL differential cell counts, whilst a slight but significant increase of the percentage of lymphocytes was observed in samples with mild blood contamination. Mucus and variable numbers of ciliated epithelial cells were commonly present. Rarely, multinucleated macrophages and mastocytes were also observed. The reference intervals established in this study provide a useful baseline for the assessment of BAL cytological data in cynomolgus macaques.

Revised recommendations for health monitoring of non-human primate colonies (2018): FELASA Working Group Report.

The genetic and biological similarity between non-human primates and humans has ensured the continued use of primates in biomedical research where other species cannot be used. Health-monitoring programmes for non-human primates provide an approach to monitor and control both endemic and incoming agents that may cause zoonotic and anthroponotic disease or interfere with research outcomes. In 1999 FELASA recommendations were published which aimed to provide a harmonized approach to health monitoring programmes for non-human primates. Scientific and technological progress, understanding of non-human primates and evolving microbiology has necessitated a review and replacement of the current recommendations. These new recommendations are aimed at users and breeders of the commonly used non-human primates; Macaca mulatta (Rhesus macaque) and Macaca fascicularis (Cynomolgus macaque). In addition, other species including Callithrix jacchus (Common marmoset) Saimiri sciureus (Squirrel monkey) and others are included. The important and challenging aspects of non-human primate health-monitoring programmes are discussed, including management protocols to maintain and improve health status, health screening strategies and procedures, health reporting and certification. In addition, information is provided on specific micro-organisms and the recommended frequency of testing.

Convergence Insufficiency Identifies Athletes at Risk of Prolonged Recovery From Sport-Related Concussion.

BACKGROUND: Sensitive and specific screening methods are needed to identify athletes at risk of prolonged recovery after sport-related concussion (SRC). Convergence insufficiency (CI) is a common finding in concussed athletes. PURPOSE: To assess the relationship between CI and recovery after SRC at the initial office visit. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: In this retrospective cohort study, 270 athletes (147 male, 123 female), mean ± SD age 14.7 ± 2.0 years (range, 10-21 years), with the diagnosis of SRC who presented for initial office visit between January 2014 and January 2016 were evaluated for near point of convergence (NPC). The athletes were categorized into 2 groups: normal near point of convergence (NPC ≤6 cm), and convergence insufficiency (NPC >6 cm). These athletes were then followed to determine recovery time. RESULTS: Athletes presented for initial office visit at a mean of 5.2 ± 4.2 days (range, 1-21 days) after SRC. Half of the athletes had CI after SRC (50.4%; n = 136). Athletes with CI (NPC 12.3 ± 4.7 cm) took significantly longer to recover after SRC, requiring 51.6 ± 53.9 days, compared with athletes with normal NPC (4.1 ± 1.3 cm), who required 19.2 ± 14.7 days ( P < .001). After controlling for potential confounding variables, CI significantly increased the odds of prolonged recovery (≥28 days from injury) by 12.3-fold ( P < .001; 95% confidence interval, 6.6-23.0). CI screening correctly classified 75.2% of our sample with 84.2% sensitivity and 70.0% specificity. The positive predictive value for CI and prolonged recovery was 62.5%, and the negative predictive value was 88.1%. CONCLUSION: CI at the initial office visit identified athletes at increased risk of prolonged recovery after SCR. Clinicians should consider measuring NPC in concussed athletes as a quick and inexpensive prognostic screening method.

Baseline Time to Stabilization Identifies Anterior Cruciate Ligament Rupture Risk in Collegiate Athletes.

BACKGROUND: There is a need for successful screening methods to identify athletes at increased risk of anterior cruciate ligament (ACL) injury. Previous research showed that collegiate athletes with ACL tears demonstrated slower time to stabilization during jump landing after reconstruction. HYPOTHESIS: Collegiate athletes with baseline deficiencies in time to stabilization are at increased risk of subsequent ACL rupture. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A total of 278 National Collegiate Athletic Association Division I college athletes (166 men, 112 women; mean age, 18.5 years; height, 178.8 cm; mass, 79.9 kg) in the high-risk sports of men's football; women's volleyball and field hockey; and men's and women's lacrosse, basketball, and soccer were measured to obtain baseline time to stabilization for backward, forward, medial, and lateral single-legged jump landing tasks. Athletes were followed for ACL rupture over a 4-year period. Independent t tests were used to evaluate differences in time to stabilization for each jump landing task between athletes with subsequent ACL rupture and uninjured athletes. Logistic regression models were used to assess time to stabilization as a predictor for ACL rupture. RESULTS: Nine athletes sustained noncontact ACL ruptures (5 men, 4 women). These 9 athletes took significantly longer to stabilize compared with uninjured athletes during baseline backward jump landing (1.58 ± 0.39 and 1.09 ± 0.52 seconds, respectively; P = .0052). The odds of ACL rupture increased 3-fold (odds ratio, 2.95; 95% CI, 1.28-6.77) for every second increase in backward time to stabilization observed between injured and uninjured athletes. CONCLUSION: Collegiate athletes with slower baseline backward time to stabilization were at increased risk of ACL rupture.

Reference intervals, intraindividual and interindividual variability, and reference change values for hematologic variables in laboratory beagles.

In research and development studies for human and veterinary medicine, relevant comparators for interpreting clinical pathology results are matched with concurrent control animals. However, reference intervals (RI) provide a comparator database and important aids for interpreting clinical pathology data, especially in laboratory beagle dogs. Furthermore, RI incorporate biologic variation, which includes analytical, intraindividual, and interindividual variation. No studies to date have established RI and studied the effect of biologic variation on hematologic variables in a large group of laboratory dogs. The purpose of this retrospective study was to establish hematologic RI for laboratory beagles according to international recommendations and estimate the effect of biologic variation in routinely measured hematologic analytes by using the databank at a pharmaceutical center. Blood specimens from 340 healthy beagles (age, 9 to 36 mo) were evaluated by using a flow-cytometry-based hematology analyzer. RI and their 90% confidence intervals were established by using a nonparametric method. Effects of sex, age, and weight were investigated. Weight had no effect on any analyte. RBC, Hgb, Hct, MCV, MCH, RBC distribution width, and platelet count increased with age, whereas WBC count decreased. The only clinically relevant effect of sex was observed for platelets, which were lower in male beagles than in female and warranted 2 different RI. The calculated index of individuality showed that population-based RI were appropriate for almost all hematologic analytes, as might be expected for a homogeneous group of laboratory beagles.

Lyme disease in athletes.

Lyme disease, a bacterial infection transmitted by ticks, is the most common vector-borne disease in the northern hemisphere. Athletes who train or compete in wooded environments in endemic regions are at increased risk of contracting Lyme disease. Variability in clinical presentation, masquerading symptoms, and limitations in testing may lead to misdiagnosis. Early diagnosis and treatment result in full recovery for most patients with Lyme disease; however symptoms may persist for months to years, especially when diagnosis is delayed. This article reviews the epidemiology, clinical manifestations, diagnosis, treatment, and prevention of Lyme disease, with focus on the athletic population.

Pyelonephritis and Bacteremia from Lactobacillus delbrueckii.

Lactobacilli are normal colonizers of the oropharynx, gastrointestinal tract, and vagina. Infection is rare, but has been reported in individuals with predisposing conditions. Here we describe the case of a woman with pyelonephritis and bacteremia in which Lactobacillus delbrueckii was determined to be the causative agent.

Sudden cardiac arrest and death in United States marathons.

PURPOSE: There is no reporting system for marathon-associated sudden cardiac arrest (SCA) or sudden cardiac death in the United States. The purpose of this study was to estimate and characterize the risk of marathon-related SCA to assist with emergency planning. METHODS: A retrospective Web-based survey was sent out to all US marathon medical directors (n = 400) to gather details of SCA including demographics, resuscitation efforts, mortality, and autopsy results, if available. RESULTS: A total of 88 surveys (22%) were returned from marathons run from 1976 to 2009 for a total of 1,710,052 participants. Risks of SCA and sudden cardiac death were 1 in 57,002 and 1 in 171,005, respectively. Men made up the vast majority of SCA victims (93%, mean age = 49.7 yr, range = 19-82 yr). Arrest site distributions were 0-5, 6-14, 15-22, and 23-26.2 miles. CAD was reported as the cause of death at autopsy in 7 of the 10 fatalities. An automated external defibrillator (AED) was used in 20/30 cases and associated with a higher survival (17/20 survivors vs 3/10 deaths, P = 0.0026). CONCLUSIONS: SCA occurs in approximately 1 in 57,000 marathon runners, is more common in older males, and usually occurs in the last 4 miles of the racecourse. Prompt resuscitation including early use of an AED improves survival. Emergency planning to include trained medical staff and sufficient AEDs throughout the racecourse is recommended.

Ménétrier disease in an acquired immunodeficiency syndrome patient.

Ménétrier disease is a rare disorder of unknown etiology. An overexpression of TGF-alpha has been proposed to play a role in the pathophysiology. HIV-1 tat gene product has been shown to stimulate TGF-alpha production leading to a positive feedback autocrine loop. The case of a 41-year-old male with AIDS who presented with weight loss, abdominal pain, ascites, edema, nausea, vomiting, and diarrhea is discussed. A computed tomography (CT) scan of the abdomen showed avid enhancement of the stomach mucosa. Magnetic resonance angiography revealed gastric and small bowel distention with diffuse wall thickening. Biopsies of the stomach showed marked foveolar hyperplasia with active inflammation and gland changes consistent with Ménétrier disease.

Noggin producing, MyoD-positive cells are crucial for eye development.

A subpopulation of cells expresses MyoD mRNA and the cell surface G8 antigen in the epiblast prior to the onset of gastrulation. When an antibody to the G8 antigen was applied to the epiblast, labeled cells were later found in the ocular primordia and muscle and non-muscle forming tissues of the eyes. In the lens, retina and periocular mesenchyme, G8-positive cells synthesized MyoD mRNA and the bone morphogenetic protein inhibitor Noggin. MyoD expressing cells were ablated in the epiblast by labeling them with the G8 MAb and lysing them with complement. Their ablation in the epiblast resulted in eye defects, including anopthalmia, micropthalmia, altered pigmentation and malformations of the lens and/or retina. The right eye was more severely affected than the left eye. The asymmetry of the eye defects in ablated embryos correlated with differences in the number of residual Noggin producing, MyoD-positive cells in ocular tissues. Exogenously supplied Noggin compensated for the ablated epiblast cells. This study demonstrates that MyoD expressing cells serve as a Noggin delivery system to regulate the morphogenesis of the lens and optic cup.

Subfertility in mice harboring a mutation in betaB2-crystallin.

PURPOSE: betaB2-crystallin is one of the most abundant proteins of the adult ocular lens of mammals although it is expressed at lower levels in several extralenticular locations. While mutations in betaB2-crystallin are known to result in lens opacities, alterations in tissues besides the lens have not been previously investigated in these mutants. Since we found mice harboring the Crybb2Phil mutation bred poorly, here we assess the contribution of betaB2-crystallin to mouse fertility and determine the expression pattern of betaB2-crystallin in the testis. METHODS: The expression pattern of betaB2-crystallin in the testis was analyzed by rt-PCR, western blotting, and immunohistochemistry. The fecundity of wildtype and Crybb2Phil mice was analyzed by quantitative fertility testing. The morphology of testes and ovaries was assessed by hematoxylin and eosin staining. RESULTS: In the mouse testis, betaB2-crystallin mRNA is found at low levels at birth, but its expression upregulates in this tissue as the testis is primed to initiate spermatogenesis. Western blotting detected betaB2-crystallin protein in sperm obtained from mice, cattle, and humans while immunolocalization detected this protein in developing sperm from the spermatocyte stage onward. Male and female mice homozygous for a 12 nucleotide inframe deletion mutation in betaB2-crystallin are subfertile when analyzed on a Swiss Webster derived background due to defects in egg and sperm production. However, mice harboring the same mutation on the C57Bl/6 genetic background did not exhibit any defects in reproductive function. CONCLUSIONS: betaB2-crystallin is expressed in developing and mature sperm and mice of both sexes harboring the Philly mutation in the betaB2-crystallin gene are subfertile when analyzed on a Swiss Webster genetic background. While these data are suggestive of a role for betaB2-crystallin in fertility, definitive determination of this will await the creation of a betaB2-crystallin null mouse.