Identification of equine mares as reservoir hosts for pathogenic species of Leptospira.

Equine leptospirosis can result in abortion, stillbirth, neonatal death, placentitis, and uveitis. Horses can also act as subclinical reservoir hosts of infection, which are characterized as asymptomatic carriers that persistently excrete leptospires and transmit disease. In this study, PCR and culture were used to assess urinary shedding of pathogenic Leptospira from 37 asymptomatic mares. Three asymptomatic mares, designated as H2, H8, and H9, were PCR-positive for lipL32, a gene specific for pathogenic species of Leptospira. One asymptomatic mare, H9, was culture-positive, and the recovered isolate was classified as L. kirschneri serogroup Australis serovar Rushan. DNA capture and enrichment of Leptospira genomic DNA from PCR-positive, culture-negative samples determined that asymptomatic mare H8 was also shedding L. kirschneri serogroup Australis, whereas asymptomatic mare H2 was shedding L. interrogans serogroup Icterohaemorrhagiae. Sera from all asymptomatic mares were tested by the microscopic agglutination test (MAT) and 35 of 37 (94.6%) were seropositive with titers ranging from 1:100 to 1:3200. In contrast to asymptomatic mares, mare H44 presented with acute spontaneous abortion and a serum MAT titer of 1:102,400 to L. interrogans serogroup Pomona serovar Pomona. Comparison of L. kirschneri serogroup Australis strain H9 with that of L. interrogans serogroup Pomona strain H44 in the hamster model of leptospirosis corroborated differences in virulence of strains. Since lipopolysaccharide (LPS) is a protective antigen in bacterin vaccines, the LPS of strain H9 (associated with subclinical carriage) was compared with strain H44 (associated with spontaneous abortion). This revealed different LPS profiles and immunoreactivity with reference antisera. It is essential to know what species and serovars of Leptospira are circulating in equine populations to design efficacious vaccines and diagnostic tests. Our results demonstrate that horses in the US can act as reservoir hosts of leptospirosis and shed diverse pathogenic Leptospira species via urine. This report also details the detection of L. kirschneri serogroup Australis serovar Rushan, a species and serotype of Leptospira, not previously reported in the US.

Longitudinal associations between neighborhood safety and adolescent adjustment: The moderating role of affective neural sensitivity.

Research on social determinants of health has highlighted the influence of neighborhood characteristics (e.g., neighborhood safety) on adolescents' health. However, it is less clear how changes in neighborhood environments play a role in adolescent development, and who are more sensitive to such changes. Utilizing the first three waves of data from the Adolescent Brain Cognitive Development (ABCD) project (N = 7932, M (SD) age = 9.93 (.63) years at T1; 51% boys), the present study found that increases in neighborhood safety were associated with decreased adolescent externalizing symptoms, internalizing symptoms, but not sleep disturbance over time, controlling for baseline neighborhood safety. Further, adolescents' insula and anterior cingulate cortex (ACC) reactivity to positive emotional stimuli moderated the association between changes in neighborhood safety and adolescent adjustment. Among youth who showed higher, but not lower, insula and ACC reactivity to positive emotion, increases in neighborhood safety were linked with better adjustment. The current study contributes to the differential susceptibility literature by identifying affective neural sensitivity as a marker of youth's susceptibility to changes in neighborhood environment. The findings highlight the importance of neighborhood safety for youth during the transition to adolescence, particularly for those with heightened affective neural sensitivity.

The effect of pre-dosing with metformin on the insulin response to oral sugar in insulin-dysregulated horses.

BACKGROUND: A single dose of metformin administered 1 h prior to oral glucose challenge was previously shown to reduce insulinaemic responses in horses with experimentally-induced insulin dysregulation (ID). Targeted administration could be useful for controlling post-prandial hyperinsulinaemia in horses with naturally-occurring ID. OBJECTIVES: The objective was to compare the insulinaemic and glycaemic responses to oral sugar testing (OST) performed at different intervals after a single dose of metformin in horses with naturally-occurring ID. We hypothesised that pre-treatment with one dose of metformin would significantly decrease the insulinaemic response to OST. STUDY DESIGN: Randomised cross-over in vivo experiment. METHODS: Eight university-owned adult horses with naturally-occurring ID underwent OST 1, 2 and 6 h following a single oral dose of metformin (30 mg/kg) or 1 h after placebo (240 mL water) with a 7-day washout between treatments over a period of 3 weeks. Plasma insulin, C-peptide and glucose concentrations were measured at 0, 60 and 90 min after 0.45 mL/kg light corn syrup and the effect of treatment (and the interval since dosing) examined using a mixed effects linear regression model. RESULTS: Metformin treatment had no significant effect on plasma glucose, insulin or C-peptide concentrations at any time point compared with placebo (p > 0.05). For OST 1 h post metformin, median (IQR) plasma insulin was 91.3 (62.4-114.9) µIU/mL at 60 min versus 76.2 (59.1-134.5) for placebo (p = 0.8) and 62.7 (31.4-109.7) at 90 min versus 51.8 (29.2-126.3) for placebo (p = 0.9). MAIN LIMITATIONS: Small sample size may limit identification of more subtle decreases in insulin concentration with metformin pre-dosing. The results of this study are relevant only for one pre-treatment dose (30 mg/kg) which limits extrapolation to predictions about the effects of longer-term metformin administration on insulin and glucose dynamics in the horse. CONCLUSIONS AND CLINICAL IMPORTANCE: The results do not support the use of targeted metformin treatment to reduce post-prandial hyperinsulinaemia in horses with naturally-occurring ID.

Sleep and Daily Affect and Risk for Major Depression: Day-to-day and Prospective Associations in Late Adolescence and Early Adulthood.

PURPOSE: Poor sleep is associated with short-term dysregulation of mood and is a risk factor for major depressive disorder (MDD). This study examines whether objectively measured sleep in late adolescence prospectively predicts major depressive episode (MDE) onset in early adulthood as well as whether daily affect mediates this association. METHODS: The present study draws on subjective and objective sleep data, ecological momentary assessment, and diagnostic data from the longitudinal Youth Emotion Project to examine whether: a) short sleep predicts dysregulated ecological momentary assessment-measured mood the next day; b) sleep predicts depressive episodes over the subsequent 5 years; and c) dysregulated daily moods mediate the associations between short sleep and later MDD. Fixed effects, logistic regression, and formal mediation analyses were employed. RESULTS: Our results showed that nights with less sleep are followed by days with more negative affect; short sleep predicted MDEs over the subsequent 5 years (adjusting for prior MDD); and negative affect mediates the relationship between short sleep and later MDEs. DISCUSSION: Overall, our findings show sleep to be an important risk factor and hence a promising point of intervention for improving mood and reducing the risk of future MDEs in adolescents and early adults.

Age Disparities in Prevalence of Anxiety and Depression Among US Adults During the COVID-19 Pandemic.

Importance: High levels of anxiety and depression were documented shortly after the arrival of the COVID-19 pandemic and were more prevalent in younger adults than in older adults. Knowing whether these age disparities persisted throughout multiple years of the COVID-19 pandemic and identifying associated factors will help guide health policy. Objective: To investigate age disparities in anxiety and depression during the COVID-19 pandemic. Design, Setting, and Participants: This cross-sectional study consisted of a nationally representative online survey administered between April 2020 and August 2022 and included US adults who were not incarcerated. Data were analyzed between March and September 2022. Exposures: The first 27 months of the COVID-19 pandemic included wide variation in infection rates, turbulence in US political and social life, and geopolitical instability. Primary exposures include individuals' age and economic precarity and pandemic-related events (eg, weekly state-level case counts and individual vaccination status). Main outcomes and measures: Symptoms of anxiety and depression were assessed via responses to 2-item screeners (Generalized Anxiety Disorder 2-item for anxiety and Patient Health Questionnaire-2 for depression). An individual's symptoms were identified as clinically elevated if scores exceeded validated thresholds. Results: This study included 3 028 923 respondents (mean [SD] age, 48.9 [17.0] years; 1 567 603 [51.8%] female). In multiple regression analyses that include state fixed effects and survey-week fixed effects, likely anxiety and depressive disorders among 291 382 (40%) and 238 505 (33%) of adults aged 18 to 39 years, respectively, compared with 357 820 (31%) and 274 534 (24%) of adults aged 40 to 59 years and 225 295 (20%) and 183 695 (16%) adults aged 60 years and older. Levels declined throughout the pandemic period for those aged 40 years and older but remained elevated for younger adults. Analyses identified several associated factors of these age disparities. Younger adults' anxiety and depression increased more than older adults' after surges in COVID-19 case counts but decreased less following vaccination against the virus. Additionally, approximately one third of the age gap among individuals with depression and anxiety was attributed to economic precarity, to which younger adults are disproportionately exposed. Conclusions and relevance: In this cross-sectional study of anxiety and depression during the COVID-19 pandemic, economic precarity was associated with high anxiety and depression among younger adults in the US compared with older adults in the US. These findings suggest a need for greater mental health care and economic policies targeted toward younger adults.

The Effect of Inhaled Ciclesonide Treatment on Systemic Markers of Immune Function in Horses.

The use of dexamethasone to control equine asthma is a common and effective treatment. Although short-term systemic dexamethasone treatment has not been shown to induce systemic immunosuppression in the horse, the goal of this study was to determine whether inhaled ciclesonide, an FDA-approved drug for the treatment of equine asthma, exerts any systemic immunosuppressive effects when compared to dexamethasone-treated and untreated horses. Eighteen light, mixed breed horses, ranging in age from 3 to 8 years of age, were used for this study and randomly assigned to one of three treatment groups: (1) nontreated controls, (2) ciclesonide treatment, or (3) dexamethasone treatment. Blood was collected daily for steady-state messenger RNA (mRNA) analysis, as well as at Days 0, 5, 10, and 15 of treatment for in vitro stimulation with Concanavalin A (ConA). Messenger RNA relative quantities were determined using RT-qPCR for select genes. Two-way, repeated measures analysis of variance was used to analyze qPCR data and results considered significant at P < .05. There were significant decreases in the steady-state, whole-blood expression of granzyme B and interferon-γ due to dexamethasone treatment, when compared to the nontreated control group. Within ConA-stimulated samples, there remained a suppressive effect of dexamethasone treatment on granzyme B expression compared to nontreated control horses. Similar effects were not noted in the ciclesonide-treated horses. Significant effects of ciclesonide treatment on markers of immune function were not noted in this study, suggesting a low risk for immunosuppression with inhaled ciclesonide treatment.

Effects of High-Speed Training on Messenger RNA Expression in Two-Year-Old Thoroughbred Racehorses.

Accumulating high-speed exercise has been identified as a significant risk factor for catastrophic injuries in racing Thoroughbreds. Injuries, regardless of severity, are a main cause of withdrawal from the racing industry, raising animal welfare concerns and resulting in significant economic losses. While most of the current literature focuses on injuries incurred during racing rather than training, the present study aims to help fill this gap. As such, peripheral blood was collected weekly, prior to exercise or administration of medication, from eighteen, two-year-old Thoroughbreds throughout their first season of race training. Messenger RNA (mRNA) was isolated and used to analyze the expression of 34 genes via RT-qPCR. Statistical analysis of the noninjured horses (n = 6) showed that 13 genes were significantly correlated with increasing average weekly high-speed furlong performance. Additionally, there was a negative correlation for CXCL1, IGFBP3, and MPO with both cumulative high-speed furlongs and week of training for all horses. Comparison of both groups showed opposing correlations between the anti-inflammatory index (IL1RN, IL-10, and PTGS1) and average weekly high-speed furlong performance. Furthermore, evaluation of training effects on mRNA expression during the weeks surrounding injury, showed differences between groups in IL-13 and MMP9 at -3 and -2 weeks prior to injury. While some previously reported relationships between exercise adaptation and mRNA expression were not noted in this study, this may have been due to the small sample size. Several novel correlations, however, were identified and warrant further investigation as markers of exercise adaptation or potential risk for injury.

Daily experiences and adolescent affective wellbeing during the COVID-19 pandemic: The CHESS model.

The COVID-19 pandemic resulted in adolescents' increased exposure to daily experiences of risk factors for depression and anxiety (e.g., loneliness). Intensive longitudinal studies examining daily experiences during the pandemic have revealed short-term and long-term consequences on youth mental health. Although evidence suggests small average increases in adolescent depression and anxiety, most of the story is in variability: increases are higher for youth and families with greater pre-existing mental health vulnerabilities and fewer socioeconomic resources, whereas increases are lower when social or financial support and positive coping and health behaviors are available and employed. Public health and economic policies should be mindful of youth mental health risks and actively promote known mental health supports, including family economic resources, access to mental healthcare, and social connection.

Equine rotaviruses - an update from Kentucky.

Emma Adam of the Gluck Equine Research Center at the University of Kentucky in the USA provides an update on rotaviruses, particularly the group B equine rotavirus identified in 2021.

Experiences of adversity in childhood and adolescence and cortisol in late adolescence.

Early life adversity influences the diurnal cortisol rhythm, yet the relative influence of different characteristics of adversity remains unknown. In this study, we examine how developmental timing (childhood vs. adolescence), severity (major vs. minor), and domain of early life adversity relate to diurnal cortisol rhythms in late adolescence. We assessed adversity retrospectively in early adulthood in a subsample of 236 participants from a longitudinal study of a diverse community sample of suburban adolescents oversampled for high neuroticism. We used multilevel modeling to assess associations between our adversity measures and the diurnal cortisol rhythm (waking and bedtime cortisol, awakening response, slope, and average cortisol). Major childhood adversities were associated with flatter daily slope, and minor adolescent adversities were associated with greater average daily cortisol. Examining domains of childhood adversities, major neglect and sexual abuse were associated with flatter slope and lower waking cortisol, with sexual abuse also associated with higher cortisol awakening response. Major physical abuse was associated with higher waking cortisol. Among adolescent adversities domains, minor neglect, emotional abuse, and witnessing violence were associated with greater average cortisol. These results suggest severity, developmental timing, and domain of adversity influence the association of early life adversity with stress response system functioning.

Residual effects of intra-articular betamethasone and triamcinolone acetonide in an equine acute synovitis model.

BACKGROUND: Intra-articular (IA) corticosteroids are regularly used in equine athletes for the control of joint inflammation. OBJECTIVES: The goal of this study was to use an acute synovitis inflammation model to determine the residual effects of IA betamethasone and triamcinolone acetonide on various inflammatory parameters and lameness. STUDY DESIGN: Crossover randomised trial. METHODS: Five mixed-breed, 2-year-old horses were randomly allocated to an IA treatment of the radiocarpal joint with 9 mg of either betamethasone or triamcinolone acetonide. Two weeks following treatment, horses were injected with 1 µg of lipopolysaccharide (LPS) diluted in 1 ml of saline. Following LPS injection, horses were crossed-over and both sets of injections were repeated after a washout period. Blood samples were collected at multiple time points for mRNA analysis, as well as serum amyloid A (SAA) and cortisol determination. At each time point, lameness was also subjectively scored. Additional injections with saline-only or LPS-only (twice) were conducted as negative and positive controls, respectively. Two-way repeated measures analysis of variance was used to analyse all data. RESULTS: Corticosteroid-only treatments result in significant mRNA expression differences, as well as significant and prolonged cortisol suppression. Following LPS injection, there was a residual treatment effect with triamcinolone evidenced by a significant treatment effect on IL-6 and PTGS1 (cyclooxygenase-1), lameness, SAA and cortisol concentrations, while only IL-6 expression was affected by betamethasone. MAIN LIMITATIONS: The acute synovitis model used here results in significant inflammation and is not representative of the low-grade inflammation seen with typical joint disease and residual anti-inflammatory effects may be more profound in naturally occurring joint disease. CONCLUSIONS: Current regulatory guidelines may be insufficient if the concern is residual anti-inflammatory effects. Additionally, intra-articular corticosteroid administration is not without risk, as evidenced by a significant suppression of serum cortisol concentration and, as such, the benefits of their administration should be weighed against those risks.

Evaluation and update of the expert consensus guidelines for the assessment of the cortisol awakening response (CAR).

The cortisol awakening response (CAR) is frequently assessed in psychobiological (stress) research. Obtaining reliable CAR data, however, requires careful attention to methodological detail. To promote best practice, expert consensus guidelines on the assessment of the CAR were published (Stalder et al., 2016, PNEC). However, it is unclear whether these highly cited guidelines have resulted in actual methodological improvements. To explore this, the PNEC editorial board invited the present authors to conduct a critical evaluation and update of current CAR methodology, which is reported here. (i) A quantitative evaluation of methodological quality of CAR research published in PNEC before and after the guidelines (2013-2015 vs. 2018-2020) was conducted. Disappointingly, results reveal little improvement in the implementation of central recommendations (especially objective time verification) in recent research. (ii) To enable an update of guidelines, evidence on recent developments in CAR assessment is reviewed, which mostly confirms the accuracy of the majority of the original guidelines. Moreover, recent technological advances, particularly regarding methods for the verification of awakening and sampling times, have emerged and may help to reduce costs in future research. (iii) To aid researchers and increase accessibility, an updated and streamlined version of the CAR consensus guidelines is presented. (iv) Finally, the response of the PNEC editorial board to the present results is described: potential authors of future CAR research to be published in PNEC will be required to submit a methodological checklist (based on the current guidelines) alongside their article. This will increase transparency and enable reviewers to readily assess the quality of the respective CAR data. Combined, it is hoped that these steps will assist researchers and reviewers in assuring higher quality CAR assessments in future research, thus yielding more reliable and reproducible results and helping to further advance this field of study.

Maternal stress and mental health before pregnancy and offspring diurnal cortisol in early childhood.

The current study investigates whether prepregnancy maternal posttraumatic stress disorder (PTSD) symptoms, depressive symptoms, and stress predict children's cortisol diurnal slopes and cortisol awakening responses (CARs) adjusting for relevant variables. Mothers were enrolled after delivering a baby and followed through their subsequent pregnancy with 5 years of longitudinal data on their subsequent child. This prospective design allowed assessment of PTSD symptoms, depressive symptoms, and perceived stress prior to pregnancy. Children provided three saliva samples per day on three consecutive days at two timepoints in early childhood (M age = 3.7 years, SD = 0.38; M age = 5.04 years, SD = 0.43). Mothers' PTSD symptoms prior to pregnancy were significantly associated with flatter child diurnal cortisol slopes at 4 and 5 years, but not with child CAR. Findings at the age of 4 years, but not 5 years, remained statistically significant after adjustment for maternal socioeconomic status, race/ethnicity, child age, and other covariates. In contrast, maternal prepregnancy depressive symptoms and perceived stress did not significantly predict cortisol slopes or CAR. Results suggest that maternal prepregnancy PTSD symptoms may contribute to variation in early childhood physiology. This study extends earlier work demonstrating risk of adverse outcomes among children whose mothers experienced trauma but associations cannot be disentangled from effects of prenatal mental health of mothers on children's early childhood.

Diurnal cortisol variation during pregnancy in Turkish origin and non-migrant women in a German birth cohort study.

BACKGROUND: Immigrants from Turkey experience health disadvantages relative to non-immigrant populations in Germany that are manifest from the earliest stages of the lifespan onwards and are perpetuated across generations. Chronic stress and perturbations of stress-responsive physiological systems, including the hypothalamus-pituitary-adrenal (HPA)-axis, are believed to in part mediate this relationship. Cortisol plays an important role in the association between maternal stress during pregnancy and many pregnancy-, birth- and offspring-related outcomes. We therefore examined whether maternal migrant background is associated with diurnal cortisol variation during pregnancy. METHODS: 109 pregnant women (incl. n = 32 Turkish origin women) that participated in a multi-site prospective cohort study in Germany collected saliva samples across the day on two consecutive days around 24 and 32 weeks gestation. Hierarchical linear models were applied to quantify associations between migrant background and diurnal cortisol variation across pregnancy. RESULTS: Women of Turkish origin exhibited a significantly lower cortisol awakening response (CAR) and a flatter diurnal cortisol slope (DCS) compared to non-migrant women after adjusting for household income. These relationships between migrant status and diurnal cortisol variation were mainly driven by 2nd generation migrants. DISCUSSION: A potential HPA axis dysregulation of Turkish-origin pregnant women may contribute to the intergenerational transmission of health disadvantages in this group.

The intersection of race and socioeconomic status is associated with inflammation patterns during pregnancy and adverse pregnancy outcomes.

BACKGROUND: Preterm birth rates are higher among individuals of lower socioeconomic status and non-White race, which is possibly related to life-course stressors. It is important to understand the underlying mechanisms of these health disparities, and inflammation is a possible pathway to explain the disparities in birth outcomes. OBJECTIVE: In this study, we aimed to determine whether patterns of inflammation differed by maternal race and socioeconomic status. STUDY DESIGN: Seven hundred and forty-four participants in a multi-site, prospective study of pregnancy and birth outcomes provided biological and psychological data between 12'0-20'6 weeks gestation. Participants with recent infection, fever, antibiotics or steroid treatment were excluded. Cytokines including INFÉ£, IL-10, IL-13, IL-6, IL-8, and TNFα, and the acute phase protein CRP were measured in serum and values and were log-transformed for normality when appropriate, and a non-orthogonal rotation (Oblimid) was performed to allow the extracted factor to inter-correlate. IFNγ, IL-8, IL-10, IL-6, TNF-a, and IL-13 loaded onto Inflammatory Factor 1 (IF-1), while CRP and IL-6 loaded onto Inflammatory Factor 2 (IF-2). Race and education were collected via self-report during an in-person study visit. Multivariable models were used to determine the association of race and SES with IF-1 and IF-2 during the second trimester, and a mediation model was used to examine if inflammation is on the causal pathway. Models were adjusted for study site, prenatal age, pre-pregnancy BMI, smoking during pregnancy, and gestational age at the time of blood collection. RESULTS: Six hundred and five participants were included in our final analysis, with 61.2% of low or moderate SES, and 35.5% identifying as a person of color (POC). Identifying as a POC, being of low and moderate SES, and being both low-SES and POC or moderate-SES and POC were associated with higher odds of preterm birth and lower birth weight percentile infants. Low SES POC participants had significantly higher IF-1 and IF-2 scores when compared to high-SES White participants. Additionally, higher IF-1 and IF-2 were associated with shorter gestation. In the mediation analysis, we observed a significant direct effect of race/SES on preterm birth; however, the results did not support an indirect pathway where IF-1 or IF-2 acted as mediators. CONCLUSION: Maternal race and SES are significantly associated with inflammatory biomarkers during pregnancy, and when race and SES are considered in combination, they are stronger predictors of adverse pregnancy outcomes than when evaluated separately.

Development and Use of an Enzyme-Linked Immunosorbent Assay to Determine Temporal Exposure Patterns to Putative Agents of Nocardioform Placentitis.

Cases of nocardioform placentitis are characterized by focal, mucoid placentitis resulting in late-term abortion, premature birth, or small, full-term foals, occur sporadically, and are most commonly associated with Crossiella equi and Amycolatopsis spp. infection. The goal of this project was to develop an enzyme-linked immunosorbent assay (ELISA) for quantifying antibodies against Crossiella equi and Amycolatopsis spp. and utilize the ELISA to determine when exposure occurs. Serum samples collected during the 2020 foaling season from Crossiella equi (n = 8) and Amycolatopsis spp. (n = 32) infected mares, as well as nonaffected mares (n = 51 mares), were used to develop and optimize bacteria-specific ELISAs. Following development of the ELISAs, banked serum samples from a single, central Kentucky Thoroughbred farm collected during 2012 to 2013 (n = 104 mares) and 2013-14 (n = 82 mares) were analyzed. Differences in various groups were analyzed using one-way analysis of variance (ANOVA). Crossiella equi-infected mares had significantly higher ELISA unit (EU) values on the Crossiella equi ELISA near parturition when compared to the other two groups (P < .001). Using the Amycolatopsis spp. ELISA, EU values were not significantly different between Amycolatopsis spp. infected and non-affected mares, suggesting this ELISA is not specific for Amycolatopsis spp. During 2013 to 2014, there were significant increases in EU values between June and late September for the Crossiella equi ELISA, suggesting exposure in the summer and early fall months. Data from the Crossiella equi ELISA may help provide a better understanding of the epidemiology of nocardioform placentitis, guide the development of a successful experimental challenge model, and allow for further refinement of these ELISAs.

Equine Peripheral Gene Expression Changes in Response to Dose-Dependent Lipopolysaccharide-Induced Synovitis.

The use of lipopolysaccharide to induce a localized source of inflammation (acute synovitis) and allow for monitoring of changes in systemic mRNA expression has been recently reported. Here, the goal was to maintain a significant systemic mRNA response while limiting the severity of lameness such that this model can be used to examine the effects of various anti-inflammatory treatment modalities on mRNA expression. Three mixed breeds, four-year-old geldings were utilized for this study. One milliliter of phosphate-buffered saline containing 1,000 ng or less of lipopolysaccharide from E. coli O111:B4 was aseptically injected into alternating radiocarpal joints following washout periods. Blood for complete blood cell count, serum amyloid A concentration, and mRNA analysis via RT-qPCR for 23 different genes were collected before each injection, as well as at multiple times post-injection. Lameness severity was also graded at each time point. Two-way, repeated measures analysis of variance was used for statistical analysis (P < .05). Results largely replicated those previously reported, with multiple genes exhibiting significant expression changes during the acute inflammatory period (including increases in CD14, TLR4, IL-1ß, IL1RN, MMP1, and MMP9 expression) while some demonstrated dose-dependent changes; significant increases in complete blood cell count parameters and serum amyloid A concentrations were also noted. Attempts to temper the severity of lameness were not successful as nonweight bearing lameness was noted at doses of 10ng or higher, while a dose of 1ng elicited neither a detectable lameness nor a significant change in mRNA expression.

Expression of select mRNA in Thoroughbreds with catastrophic racing injuries.

BACKGROUND: The ability to identify horses at risk for catastrophic injuries continues to be a pressing issue for the racing industry, especially given recent events in North America. OBJECTIVES: Since most catastrophic injuries occur in areas of existing pathology and this pathology is likely to elicit an inflammatory response, it was hypothesised that analysis of messenger RNA (mRNA) expression would detect significant changes in select genes in horses at risk for a catastrophic injury. STUDY DESIGN: Prospective cohort study. METHODS: Five racing jurisdictions across the United States participated in this study. A total of 686 Tempus® RNA Blood Tube samples were collected for mRNA analysis from 107 catastrophically injured horses, as well as from noninjured horses sampled either prerace (n = 374) or postrace (n = 205). A subset of horses (n = 37) were sampled both prerace and postrace for analysis of expression changes during the postrace period. RESULTS: Of 21 genes analysed via RT-qPCR, the expression of 12 genes (ALOX5AP, CD14, IL-10, IL-1ß, IL-6, IL-8, MMP1, PTGS2, TLR4, TNFα, TNFSF13B and VEGFA) changed significantly within 45 minutes after a race and were excluded. Of the remaining nine genes (BMP-2, IGF-1, IL1RN, MMP2, MMP9, Osteoprotegrin, RANKL, SAA1 and TGFß), three genes (IGF-1, IL1RN and MMP2) were found to be significantly different between catastrophically injured and noninjured horses using multiple logistic regression modelling. Receiver operating characteristic analysis of models, which included mRNA expression, demonstrated sensitivities from 76%-82% (95% CI: 67%-93%) and specificities from 84%-88% (95% CI: 71%-94%) at the Youden Index. MAIN LIMITATIONS: Samples were collected as soon as possible postinjury (within 30 minutes). CONCLUSIONS: Analysis of mRNA expression of specific genes in the future may be considered as an economical, accessible and noninvasive means by which horses at risk for catastrophic injury can be identified.

Using principal component analysis to examine associations of early pregnancy inflammatory biomarker profiles and adverse birth outcomes.

OBJECTIVE: Inflammation as a risk factor for preterm birth is well-established. The primary objective of this analysis was to examine whether individual cytokines versus a composite indicator of mid-pregnancy inflammation are significantly associated with risk for adverse birth outcomes. STUDY DESIGN: A multi-site prospective study was conducted in a socio-demographically diverse cohort of 610 pregnant participants. At a study visit between 12 and 20 6/7 weeks' gestation, low-grade inflammation was measured via log-transformed serum concentrations of the biomarkers IFN-γ, IL-10, IL-13, IL-6, IL-8, TNF-α, and CRP. Principal component analysis (PCA) was used to identify underlying dimensions of inflammatory activity from the seven biomarkers measured. Gestational age and birth weight at delivery were obtained from medical chart review. The associations between inflammatory profiles and birth outcomes were assessed via linear and logistic regression models. Results were compared with those from individual inflammatory biomarkers, and model fit was assessed using Akaike's Information Criterion (AIC). RESULTS: Principal component analysis analysis yielded a two-factor solution, with the first factor (IF1) composed of IL-8, IL-10, IL-13, IFN-É£, and TNF-α, and the second factor (IF2) containing IL-6 and CRP. When adjusted for race, education, BMI, smoking status, gestational age at time of blood draw, and study site, a one standard deviation (SD) increase in IF1 remained significantly associated with a decrease in standardized gestational age (ß = -.13, 95% CI: -.21, -.05) and an increase in odds of preterm delivery (OR = 1.46, 95% CI: 1.13, 1.88) (Table 3). A one SD increase in IF2 was similarly associated with a decrease in standardized gestational age at delivery (ß = -.13, 95% CI: -.23, -.04) and an increase in odds of preterm delivery (OR: 1.46, 95% CI: 1.04, 2.05). Neither IF1 nor IF2 was associated with measures of fetal growth. AIC identified that IL-6 was a slightly better fit for length of gestation compared to either composite measure, though all performed similarly. CONCLUSION: Independent of known sociodemographic risk factors, an elevated mid-pregnancy inflammatory profile was associated with a nearly 50% increase in odds of preterm delivery. The composite performed similarly to IL-6. These results suggest that maternal low-grade inflammation is a risk factor for preterm delivery, and that mid-pregnancy inflammatory biomarkers may be useful in predicting risk for preterm delivery.