Temperature stability of urinary F2-isoprostane and 8-hydroxy-2'-deoxyguanosine.

Background: Clinical and epidemiological studies employ long-term temperature storage but the effect of temperature on the stability of oxidative stress (OS) markers is unknown. We investigated the effects of storage at -20 °C and -80 °C over 4-9 months on F2-isoprostanes (F2-IsoP) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in urine of children, a population group among whom the measurement of these markers is still limited. Methods: Paired spot urine samples from 87 children aged 8.9-16.9 years (52.9% boys) were analyzed. Samples were preserved with 0.005% (w/v) butylated hydroxytoluene, portioned and stored within 2.5 h (median) of collection. Samples were analyzed in duplicate or triplicate using commercial ELISA kits and their correlations were evaluated. Results: F2-IsoP and 8-OHdG showed high correlations (Spearman rho of 0.90 and 0.97, respectively; P < 0.0001) with storage at -20 °C and -80 °C. There was a strong agreement among categories of values for F2-IsoP (Kappa = 0.76 ± 0.08, agreement = 83.9%, P < 0.0001) and 8-OHdG: (Kappa = 0.83 ± 0.08, agreement = 88.4%, P < 0.0001). The correlation between the temperatures for F2-IsoP concentrations was also high when stored for <4 (0.93), 4 (0.93), and 5 months (0.88), all P < 0.0001. For 8-OHdG, Spearman correlations at <8, 8, and 9 months of storage at -20 °C and -80 °C were 0.95, 0.98, and 0.96 (all P < 0.0001), respectively. Conclusions: Urine storage with BHT for up to nine months at a temperature of -20 °C to -80 °C yields highly comparable concentrations of F2-IsoP and 8-OHdG.

Exploratory 5-year follow-up study of retinol, tocopherols, and carotenoids in multiple sclerosis.

BACKGROUND: Retinol, tocopherols, and carotenoids (RTC) have physiological roles as vitamins, pro-vitamins, and antioxidants, and provide biomarkers of dietary vegetable and fruit intake. The goal was to investigate RTC in multiple sclerosis (MS). METHODS: This exploratory study included 106 people with MS (71 relapsing-remitting MS or RR-MS; and 35 progressive MS or PMS) and 31 healthy controls (HC) at baseline and 5-year follow-up (5YFU). Serum retinol, α-carotene, ß-carotene, α-tocopherol, δ-tocopherol, γ-tocopherol, ß-cryptoxanthin, lutein/zeaxanthin, and lycopene were measured using high performance liquid chromatography. Serum neurofilament light chain (sNfL) levels were measured using the single molecule array method. Expanded Disability Status Scale (EDSS) and low contrast letter acuity (LCLA) were used as disability measures. RESULTS: Retinol in MS was positively correlated with α-carotene, ß-carotene, ß-cryptoxanthin, lutein/zeaxanthin, and α-tocopherol but negatively correlated with δ-tocopherol. EDSS was associated with α-tocopherol, δ-tocopherol, and lycopene. Greater retinol levels were associated with greater LCLA in RR-MS and PMS; high contrast visual acuity was not associated. Greater γ-tocopherol levels were associated with lower LCLA and high contrast visual acuity in PMS. CONCLUSIONS: RTC exhibit distinctive associations with LCLA and EDSS in MS.

Antioxidant defense enzymes in multiple sclerosis: A 5-year follow-up study.

BACKGROUND AND PURPOSE: Oxidative stress biomarkers are increased in multiple sclerosis (MS) lesions. Antioxidant defense enzymes regulate reactive oxygen species that can cause tissue injury in MS. METHODS: The study of 91 subjects included 64 relapsing-remitting MS (RR-MS; 72% female, baseline age ± SD = 44.6 ± 11 years, disease duration = 13.3 ± 8.8 years, median Expanded Disability Status Scale [EDSS] = 2.0, interquartile range = 1.8) and 27 healthy controls (HC) at baseline and 5-year follow-up (5YFU). Serum glutathione peroxidase (GPX), glutathione-S-transferase (GST), glutathione reductase (GSHR), superoxide dismutase, and paraoxonase-1 (PON1) arylesterase and paraoxonase activities were measured using kinetic enzyme assays. Total cholesterol (TC), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol (LDL-C), and an apolipoprotein (Apo) panel with ApoA-I, ApoA-II, ApoB, ApoC-II, and ApoE were obtained. Serum neurofilament (sNfL) was used to assess axonal injury. Disability was measured on the EDSS. RESULTS: GSHR activity was lower in HC compared to RR-MS at baseline and 5YFU. GPX (p = 0.008) and PON1 arylesterase and paraoxonase activities (both p = 0.05) increased between baseline and 5YFU in HC but did not increase in RR-MS. At baseline and 5YFU, GPX and GST were associated with TC, LDL-C, and ApoA-II; GSHR was associated with ApoA-II and ApoC-II. Antioxidant enzymes were not associated with sNfL or EDSS in RR-MS. CONCLUSIONS: RR-MS patients did not exhibit the changes in antioxidant enzyme activities over 5YFU found in HC; however, the differences were modest. Antioxidant enzyme activities are not associated with disability.

Metabolomic profiles in relapsing-remitting and progressive multiple sclerosis compared to healthy controls: a five-year follow-up study.

INTRODUCTION AND OBJECTIVES: Multiple sclerosis (MS) is a disease of the central nervous system associated with immune dysfunction, demyelination, and neurodegeneration. The disease has heterogeneous clinical phenotypes such as relapsing-remitting MS (RRMS) and progressive multiple sclerosis (PMS), each with unique pathogenesis. Metabolomics research has shown promise in understanding the etiologies of MS disease. However, there is a paucity of clinical studies with follow-up metabolomics analyses. This 5-year follow-up (5YFU) cohort study aimed to investigate the metabolomics alterations over time between different courses of MS patients and healthy controls and provide insights into metabolic and physiological mechanisms of MS disease progression. METHODS: A cohort containing 108 MS patients (37 PMS and 71 RRMS) and 42 controls were followed up for a median of 5 years. Liquid chromatography-mass spectrometry (LC-MS) was applied for untargeted metabolomics profiling of serum samples of the cohort at both baseline and 5YFU. Univariate analyses with mixed-effect ANCOVA models, clustering, and pathway enrichment analyses were performed to identify patterns of metabolites and pathway changes across the time effects and patient groups. RESULTS AND CONCLUSIONS: Out of 592 identified metabolites, the PMS group exhibited the most changes, with 219 (37%) metabolites changed over time and 132 (22%) changed within the RRMS group (Bonferroni adjusted P < 0.05). Compared to the baseline, there were more significant metabolite differences detected between PMS and RRMS classes at 5YFU. Pathway enrichment analysis detected seven pathways perturbed significantly during 5YFU in MS groups compared to controls. PMS showed more pathway changes compared to the RRMS group.

Real-World Racial Variation in Treatment and Outcomes Among Patients with Peripheral Artery Disease.

INTRODUCTION: Prior studies have found considerable disparities in prevalence and outcomes for patients with peripheral arterial disease (PAD). This study compared rates of diagnostic testing, treatment patterns, and outcomes after diagnosis of PAD among commercially insured Black and White patients in the United States. METHODS: Optum's de-identified Clinformatics® Data Mart Database (1/2016-6/2021) were used to identify Black and White patients with PAD; first PAD diagnosis was deemed study index date. Baseline demographics, markers of disease severity, and healthcare costs were compared between cohorts. Patterns of medical management and rates of major adverse limb events (MALE; including acute or chronic limb ischemia, lower-limb amputation) and cardiovascular (CV) events (stroke, myocardial infarction) during the available follow-up period were described. Outcomes were compared between cohorts using multinomial logistic regression models, Kaplan-Meier survival analysis, and Cox proportional hazards models. RESULTS: A total of 669,939 patients were identified, with 454,382 White patients and 96,162 Black patients. Black patients were younger on average (71.8 years vs. 74.2 years), but had higher comorbid burden, concomitant risk factors, and CV medication use at baseline. Prevalence of diagnostic testing, revascularization procedures, and medication use was numerically higher among Black patients. Black patients were also more likely than the White patients to receive medical therapy without a revascularization procedure [adjusted odds ratio with 95% confidence interval (CI) = 1.47 (1.44-1.49)]. However, Black patients with PAD had higher incidence of MALE and CV events than White patients [adjusted hazard ratio for composite event (95% CI) = 1.13, (1.11-1.15)]. Except myocardial infarction, the hazards of individual components of MALE and CV events were also significantly higher among Black patients with PAD. CONCLUSIONS: Results of this real-world study suggest that Black patients with PAD have higher disease severity at the time of diagnosis and are at increased risk of experiencing adverse outcomes following diagnosis.

A pilot study of the association between maternal mid-pregnancy cholesterol and oxysterol concentrations and labor duration.

BACKGROUND: Previous animal model studies have highlighted a role for cholesterol and its oxidized derivatives (oxysterols) in uterine contractile activity, however, a lipotoxic state associated with hypercholesterolemia may contribute to labor dystocia. Therefore, we investigated if maternal mid-pregnancy cholesterol and oxysterol concentrations were associated with labor duration in a human pregnancy cohort. METHODS: We conducted a secondary analysis of serum samples and birth outcome data from healthy pregnant women (N = 25) with mid-pregnancy fasting serum samples collected at 22-28 weeks of gestation. Serum was analyzed for total-C, HDL-C, and LDL-C by direct automated enzymatic assay and oxysterol profile including 7α-hydroxycholesterol (7αOHC), 7ß-hydroxycholesterol (7ßOHC), 24-hydroxycholesterol (24OHC), 25-hydroxycholesterol (25OHC), 27-hydroxycholesterol (27OHC), and 7-ketocholesterol (7KC) by liquid chromatography-selected ion monitoring-stable isotope dilution-atmospheric pressure chemical ionization-mass spectroscopy. Associations between maternal second trimester lipids and labor duration (minutes) were assessed using multivariable linear regression adjusting for maternal nulliparity and age. RESULTS: An increase in labor duration was observed for every 1-unit increment in serum 24OHC (0.96 min [0.36,1.56], p < 0.01), 25OHC (7.02 min [1.92,12.24], p = 0.01), 27OHC (0.54 min [0.06, 1.08], p < 0.05), 7KC (8.04 min [2.7,13.5], p < 0.01), and total oxysterols (0.42 min [0.18,0.06], p < 0.01]. No significant associations between labor duration and serum total-C, LDL-C, or HDL-C were observed. CONCLUSIONS: In this cohort, mid-pregnancy concentrations of maternal oxysterols (24OHC, 25OHC, 27OHC, and 7KC) were positively associated with labor duration. Given the small population and use of self-reported labor duration, subsequent studies are required for confirmation.

Maternal Pea Protein Intake Provides Sex-Specific Protection against Dyslipidemia in Offspring from Obese Pregnancies.

Increased consumption of dietary pulse protein has been shown to assist in body weight regulation and improve a range of metabolic health outcomes. We investigated if the exchange of casein for yellow pea protein (YPPN) in an obese-inducing maternal diet throughout pregnancy and lactation offered protection against obesity and dyslipidemia in offspring. Sixty female Sprague Dawley rats were fed a low-calorie control diet (CON), a high-caloric obesity-inducing diet (with casein protein (CP), HC-CP), or an isocaloric/macronutrient-matched HC diet supplemented with YPPN isolate (HC-PPN) in pre-pregnancy, gestation, and lactation. Body weight (BW) and metabolic outcomes were assessed in male and female offspring at weaning and in adulthood after consuming the CON diet in the postnatal period. Consumption of the HC-PPN diet did not protect against maternal obesity but did improve reproductive success compared with the HC-CP group (72.7% versus 43.7%) and reduced total energy, fat, and protein in maternal milk. Male, but not female, offspring from mothers fed the HC-CP diet demonstrated hyperphagia, obesity, dyslipidemia, and hepatic triglyceride (TG) accumulation as adults compared with CON offspring. Isocaloric exchange of CP for YPPN in a high-calorie obese-inducing diet did not protect against obesity but did improve several aspects of lipid metabolism in adult male offspring including serum total cholesterol, LDL/VLDL cholesterol, triglycerides (TGs), and hepatic TG concentration. Our results suggest that the exchange of CP for YPPN in a maternal obese-inducing diet selectively protects male offspring from the malprogramming of lipid metabolism in adulthood.

Cholesterol pathway biomarkers are associated with neuropsychological measures in multiple sclerosis.

BACKGROUND: Cognitive impairment (CI) is frequent in persons with multiple sclerosis (PwMS) and is linked to neurodegeneration. Cholesterol pathway biomarkers (CPB) are associated with blood-brain barrier breakdown, lesions, and neurodegeneration in multiple sclerosis (MS). CPB could influence CI. METHODS: This cross-sectional study (n = 163) included 74 relapsing-remitting MS (RR-MS), 48 progressive MS (P-MS) and 41 healthy control (HC) subjects. The assessed physical disability and cognitive measures were: Nine-hole Peg Test (NHPT), Timed 25-Foot Walk, Symbol Digit Modalities Test (SDMT), Paced Auditory Serial Addition Test-3, and Beck Depression Inventory-Fast Screen. CPB panel included plasma total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and the apolipoproteins (Apo), ApoA-I, ApoA-II, ApoB, ApoC-II and ApoE. Disability and cognitive measures were assessed as dependent variables in regression analyzes with age, sex, body mass index, years of education, HC vs. RR-MS vs. P-MS status, CPB, and a HC vs. RR-MS vs. P-MS status × CPB interaction term as predictors. RESULTS: SDMT was associated with the interaction terms for HDL-C (p = 0.045), ApoA-I (p = 0.032), ApoB (p = 0.032), TC/HDL-C (p = 0.013), and ApoB/ApoA-I (p = 0.008) ratios. CPB associations of SDMT were not abrogated upon adjusting for brain parenchymal volume. NHPT performance was associated with the interaction terms for TC (p = 0.047), LDL-C (p = 0.017), ApoB (p = 0.001), HDL-C (p = 0.035), ApoA-I (p = 0.032), ApoC-II (p = 0.049) and ApoE (p = 0.037), TC/HDL-C (p < 0.001), and ApoB/ApoA-I ratios (p < 0.001). CONCLUSIONS: The LDL to HDL proportion is associated with SDMT and NHPT in MS. The findings are consistent with a potential role for CPB in CI.

Associations of maternal lipoprotein particle distribution in mid-pregnancy with birth outcomes: a pilot study.

BACKGROUND: An excessive rise in maternal lipids during pregnancy may have detrimental impacts on maternal and fetal health leading to adverse pregnancy outcomes. However, knowledge gaps exist with respect to the association between lipid biomarkers and birth outcomes. METHODS: We conducted a secondary data analysis of healthy pregnant women (N = 25) with mid-pregnancy fasting serum samples collected at 22-28 weeks of gestation and birth outcome data. Serum was analyzed for conventional lipid profile (total-C, HDL-C, LDL-C, and triglycerides) and lipoprotein subclass distribution, including particle number (nM) and size (nm), for very low-density lipoprotein (VLDL)/chylomicron (CM), low density lipoprotein (LDL), and high-density lipoprotein (HDL), by nuclear magnetic resonance spectroscopy. Associations between maternal lipids and birth outcomes, including birth weight (g) and gestational age (weeks), were assessed using multivariable linear regression, adjusted for pre-pregnancy BMI. RESULTS: Although conventional lipids were not associated (p > 0.05) with birth outcomes, every 1-unit increment in large VLDL/CM particles (nM) and VLDL/CM size (nm) was associated with an increase in birth weight (confounder-adjusted ß-coefficient, 45.80 g [5.30, 86.20, p = 0.003] and 24.90 g [8.80, 40.90, p = 0.002], respectively). Among the HDL subclass parameters, a 1-unit (nM) increase in the concentration of total HDL-particles was associated with a reduced birth weight (confounder adjusted ß-coefficient, -19.40 g [95% confidence interval, -36.70, -2.20]; p = 0.03) after adjustment for maternal pre-pregnancy BMI. CONCLUSION: The preliminary results of this pilot study suggest that total particle concentrations of VLDL/CM and HDL in mid-pregnancy have divergent associations with birth weight, potentially reflecting the specific roles of these lipoprotein particles with respect to placental function and fetal growth.

Plasma 24-hydroxycholesterol is associated with narrower common carotid artery and greater flow velocities in relapsing multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) studies suggest greater cardiovascular disease burden and disturbances in the cholesterol pathways. The potential impact of oxidized cholesterol molecules on MS is emerging. OBJECTIVE: To determine the relationship between multiple oxysterol molecules and atherosclerosis burden in MS patients. MATERIALS AND METHODS: A total of 99 MS patients (61 relapsing-remitting MS(RRMS) and 38 progressive MS (PMS)) patients and 38 healthy controls (HCs) underwent magnetic resonance angiography (MRA) and the cross-sectional area (CSA) of the common carotid artery (CCA) was determined at three different levels before the bifurcation (C7, C6 and C5). Additionally, an echo-color Doppler ultrasound was performed and measures of blood flow velocities were derived. Blood samples acquired at the time of the imaging examinations were analyzed and 24-, 25-, 27-hydroxycholesterol (24HC, 25HC, 27HC) and 7-ketocholesterol (7KC) were quantified in ng/mL RESULTS: In the MS patients, higher levels of 24HC were significantly associated with smaller CCA CSA measured at all three cervical levels (r=-0.201, p = 0.046; r=-0.228, p = 0.023, and r=-0.215, p = 0.032, for C7, C6 and C5, respectively). These associations were driven by the RRMS group only (r=-0.407, p = 0.002 for C7; r=-0.414, p = 0.002, for C6; and r=-0.368, p = 0.006 for C5). No associations were seen in the HCs. Despite adjusting for the significant age effect (B = 0.445, p = 0.004), higher 24HC levels were independently associated with smaller CCA CSA (B=-0.20, p = 0.045). 24HC was additionally associated with greater time-averaged and peak diastolic CCA velocities. RRMS patients treated with potent anti-inflammatory therapies had lower oxysterol levels (p = 0.019). CONCLUSION: Greater 24HC levels are associated with smaller CSA CCA and greater flow velocities in RRMS patients.

Exploring Health-Related Quality of Life Burden in Peanut Allergy and the Potential Benefit of Oral Immunotherapy: Estimation of Health State Utility Values for Children and Adolescents and Their Caregivers.

Purpose: This study aimed to estimate utility values for health states relating to oral immunotherapy (OIT) for peanut allergy (PA), for children with PA and their caregivers. Patients and Methods: Two methods were used: an online survey and structured interviews. Both methods assessed current utility/untreated PA (health-related quality of life, HRQoL) and HRQoL in different health states: "up-dosing phase of treatment", "maintenance phase" and "able to tolerate 6-8 peanuts if accidentally ingested". The survey was conducted in individuals with and without experience of OIT; data collected included the EQ-5D-Y (child states) and EQ-5D-5L (caregiver states). Results: In total, 100 caregivers and 38 adolescents completed the treatment-naïve survey, a separate sample of 50 caregivers participated in structured interviews. Seven caregivers and two adolescents with experience of OIT for PA completed the survey. Data from the three samples were pooled, the mean utility values were untreated PA: 0.796 (child), 0.855 (caregiver); up-dosing: 0.711 (child), 0.806 (caregiver); maintenance: 0.821 (child), 0.849 (caregiver), tolerate 6-8 peanuts: 0.859 (child), 0.884 (caregiver). The results show a gain in utility of 0.063 for children and 0.029 for caregivers between the untreated and tolerate 6-8 peanuts health states. Conclusion: This study is the first to assess utilities relating to OIT for PA. The results show the potential benefit of OIT for individuals with PA and their caregivers and provide values for use in cost-effectiveness evaluation.

Three-Day Dietary Manipulation in Multiple Sclerosis: Exercise and Fatigue Outcomes.

BACKGROUND: In persons with multiple sclerosis (MS), the effect of nutrition on exercise performance and fatigue remains unknown. The objective was to determine whether a 3-day diet high in triglycerides (FAT) compared with a 3-day diet high in carbohydrates (CARB) would improve fatigue and exercise performance in persons with MS. METHODS: A randomized controlled crossover design was incorporated to study FAT versus CARB on submaximal cycling endurance (60% of peak oxygen consumption), substrate utilization, and fatigue in 12 persons with mild-to-moderate MS (Expanded Disability Status Scale score, 2.0-5.0) and 12 age- and sex-matched controls. RESULTS: There were no differences in cycling time between diets in either group (P = .29). The MS group had no changes in fatigue between diets (P = .64); the control group demonstrated increased total mental fatigue after FAT (P = .05). The control group increased carbohydrate oxidation by 24% at rest and 13% during exercise after CARB. Similarly, the control group significantly increased fat oxidation after FAT by 22% at rest and 68% during exercise (P = .01). These changes were not seen in the MS group. Compared with controls, persons with MS oxidized approximately 50% less fat during exercise after FAT (P = .05). CONCLUSIONS: Neither CARB nor FAT altered submaximal exercise performance or baseline fatigue in the MS group. The results suggest that persons with MS are unable to adapt to dietary changes and oxidize fatty acids as efficiently as controls.

Toxic elements in follicular fluid adversely influence the likelihood of pregnancy and live birth in women undergoing IVF.

STUDY QUESTION: Are follicular fluid (FF), arsenic (As), mercury (Hg), cadmium (Cd) and lead (Pb) concentrations associated with IVF outcomes among women undergoing IVF? SUMMARY ANSWER: There was a non-linear association between higher FF Hg concentration and a lower likelihood of biochemical pregnancy and live birth. Higher FF Pb concentration was also associated with a lower probability of live birth. WHAT IS KNOWN ALREADY: Previous research suggests that toxic elements may affect fertility among couples conceiving with and without assistance. However, the results have been inconsistent, possibly related in part to exposure misclassification. Very few studies have used ovarian FF to measure toxic elements, as it requires an invasive collection procedure, yet it may offer a more accurate estimate of a biologically effective dose than blood or urine. STUDY DESIGN SIZE DURATION: This is a prospective study of 56 women undergoing IVF, from October 2015 to June 2017. FF was collected for analysis on the day of oocyte retrieval. PARTICIPANTS/MATERIALS SETTING METHODS: As, Cd, Hg and Pb were determined in 197 FF specimens, using inductively coupled plasma tandem mass spectrometry. FF glutathione peroxidase, glutathione reductase, total glutathione-S-transferase, superoxide dismutase, arylesterase and paraoxonase (PON1p) activities were measured using kinetic enzyme assays. MAIN RESULTS AND THE ROLE OF CHANCE: Non-linear associations were detected, in which the probabilities of biochemical pregnancy (P = 0.05) and live birth (P = 0.05) were lower in association with FF Hg greater than ∼0.51 µg/l Hg, adjusted for age, race, cigarette smoking and recent seafood consumption. Higher FF Pb was also associated with a lower likelihood of live birth (relative risk (RR) = 0.68, 95% CI: 0.46, 1.00; P = 0.05). We also found a suggestive, although imprecise, antagonizing mediating effect of PON1p activity on the association between FF Pb and live birth (-28.3%; 95% CI: -358%, 270%). LIMITATIONS REASONS FOR CAUTION: The results should be interpreted judiciously given the limited sample size and difficulty accounting for correlated data in generalized additive models and mediation analyses. Additionally, women undergoing IVF are highly selected with respect to age and socioeconomic status, and so the generalizability of the results may be limited. WIDER IMPLICATIONS OF THE FINDINGS: Overall, the results suggest that FF Hg was associated with a lower likelihood of biochemical pregnancy and live birth, with a potential threshold effect, and that higher FF Pb was associated with a lower probability of live birth. These results may help to guide clinical recommendations for limiting the exposure of patients to Hg and Pb and ultimately improve IVF success rates. STUDY FUNDING/COMPETING INTERESTS: This work was funded in part by the National Institute of Environmental Health Sciences (NIEHS), grant number 1R56ES023886-01, to the University at Albany (M.S.B.), and in part by the National Institute of Environmental Health Sciences (NIEHS), grant number 1U2CES026542-01, to the Wadsworth Center (P.J.P.). The authors declare no competing interests. TRIAL REGISTRATION NUMBER: N/A.

Outcomes following acute poor-grade aneurysmal subarachnoid bleed - Is early definitive treatment better than delayed management?

BACKGROUND/OBJECTIVE: Patients with poor-grade subarachnoid bleed (World Federation of Neurosurgical Societies grades 4-5) often improve their neurocognitive function months after their ictus. However, it is essential to explore the timing of intervention and its impact on long-term outcome. We compared the long-term outcomes between immediate management within 24 h and delayed management after 24 h in patients following poor-grade subarachnoid bleed. METHODS: This was a retrospective population-based study, including patients with poor-grade subarachnoid bleed who received definitive management between 1 January 2011 and 31 December 2016 in a large tertiary neurocritical care unit. The primary outcome was adjusted odds ratio of favourable outcome (Glasgow Outcome Scale 4-5) for survivors at 12 months following discharge, as measured by the Glasgow Outcome Scale. The secondary outcomes included adjusted odds ratio of a favourable outcome at discharge, 3 months and 6 months following discharge and survival rate at 28 days, 3 months, 6 months and 12 months following haemorrhage. RESULTS: A total of 111 patients were included in this study: 53 (48%) received immediate management and 58 (52%) received delayed management. The mean time delay from referral to intervention was 14.9 ± 5.8 h in immediate management patients, compared to 79.6 ± 106.1 h in delayed management patients. At 12 months following discharge, the adjusted odds ratio for favourable outcome in immediate management versus delayed management patients was 0.96 (confidence interval (CI) = 0.17, 5.39; p = 0.961). At hospital discharge, 3 months and 6 months, the adjusted odds ratio for favourable outcome was 3.85 (CI = 1.38, 10.73; p = 0.010), 1.04 (CI = 0.22, 5.00; p = 0.956) and 0.98 (CI = 0.21, 4.58; p = 0.982), respectively. There were no differences in survival rate between the groups at 28 days, 3 months, 6 months and 12 months (71.7% in immediate management group vs. 82.8% in delayed management group at 12 months, p = 0.163). CONCLUSIONS: Immediate management and delayed management after poor-grade subarachnoid bleed are associated with similar morbidity and mortality at 12 months. Therefore, delaying intervention in poor-grade patients may be a reasonable approach, especially if time is needed to plan the procedure or stabilise the patient adequately.

Cross-validation of a high-performance liquid chromatography nevirapine plasma assay in a resource-limited setting in Zimbabwe.

An international HIV pharmacology specialty laboratory (PSL) was established at the University of Zimbabwe to increase bioanalytical and investigator capacities. Quantitation of plasma nevirapine in samples from the AIDS Clinical Trials Group protocol 5279 was compared between the University of Nebraska Medical Center PSL and the University of Zimbabwe PSL. Both PSLs employed internally developed methods utilising reverse-phase high-performance liquid chromatography with ultraviolet detection. Eighty-seven percent of the cross-validation results exhibited ± 20% difference.

Changes in arachidonic acid (AA)- and linoleic acid (LA)-derived hydroxy metabolites and their interplay with inflammatory biomarkers in response to drastic changes in air pollution exposure.

BACKGROUND: Untargeted metabolomics analyses have indicated that fatty acids and their hydroxy derivatives may be important metabolites in the mechanism through which air pollution potentiates diseases. This study aimed to use targeted analysis to investigate how metabolites in arachidonic acid (AA) and linoleic acid (LA) pathways respond to short-term changes in air pollution exposure. We further explored how they might interact with markers of antioxidant enzymes and systemic inflammation. METHODS: This study included a subset of participants (n = 53) from the Beijing Olympics Air Pollution (BoaP) study in which blood samples were collected before, during, and after the Beijing Olympics. Hydroxy fatty acids were measured by liquid chromatography/mass spectrometry (LC/MS). Native total fatty acids were measured as fatty acid methyl esters (FAMEs) using gas chromatography. A set of chemokines were measured by ELISA-based chemiluminescent assay and antioxidant enzyme activities were analyzed by kinetic enzyme assays. Changes in levels of metabolites over the three time points were examined using linear mixed-effects models, adjusting for age, sex, body mass index (BMI), and smoking status. Pearson correlation and repeated measures correlation coefficients were calculated to explore the relationships of metabolites with levels of serum chemokines and antioxidant enzymes. RESULTS: 12-hydroxyeicosatetraenoic acid (12-HETE) decreased by 50.5% (95% CI: -66.5, -34.5; p < 0.0001) when air pollution dropped during the Olympics and increased by 119.4% (95% CI: 36.4, 202.3; p < 0.0001) when air pollution returned to high levels after the Olympics. In contrast, 13-hydroxyoctadecadienoic acid (13-HODE) elevated significantly (p = 0.023) during the Olympics and decreased nonsignificantly after the games (p = 0.104). Interleukin 8 (IL-8) correlated with 12-HETE (r = 0.399, BH-adjusted p = 0.004) and 13-HODE (r = 0.342, BH-adjusted p = 0.014) over the three points; it presented a positive and moderate correlation with 12-HETE during the Olympics (r = 0.583, BH-adjusted p = 0.002) and with 13-HODE before the Olympics (r = 0.543, BH-adjusted p = 0.008). CONCLUSION: AA- and LA-derived hydroxy metabolites are associated with air pollution and might interact with systemic inflammation in response to air pollution exposure.

Differential responses of anthers of stress tolerant and sensitive wheat cultivars to high temperature stress.

MAIN CONCLUSION: Transcriptomic analyses identified anther-expressed genes in wheat likely to contribute to heat tolerance and hence provide useful genetic markers. The genes included those involved in hormone biosynthesis, signal transduction, the heat shock response and anther development. Pollen development is particularly sensitive to high temperature heat stress. In wheat, heat-tolerant and heat-sensitive cultivars have been identified, although the underlying genetic causes for these differences are largely unknown. The effects of heat stress on the developing anthers of two heat-tolerant and two heat-sensitive wheat cultivars were examined in this study. Heat stress (35 °C) was found to disrupt pollen development in the two heat-sensitive wheat cultivars but had no visible effect on pollen or anther development in the two heat-tolerant cultivars. The sensitive anthers exhibited a range of developmental abnormalities including an increase in unfilled and clumped pollen grains, abnormal pollen walls and a decrease in pollen viability. This subsequently led to a greater reduction in grain yield in the sensitive cultivars following heat stress. Transcriptomic analyses of heat-stressed developing wheat anthers of the four cultivars identified a number of key genes which may contribute to heat stress tolerance during pollen development. Orthologs of some of these genes in Arabidopsis and rice are involved in regulation of the heat stress response and the synthesis of auxin, ethylene and gibberellin. These genes constitute candidate molecular markers for the breeding of heat-tolerant wheat lines.

A framework for stability-based module detection in correlation graphs.

Graphs can be used to represent the direct and indirect relationships between variables, and elucidate complex relationships and interdependencies. Detecting structure within a graph is a challenging problem. This problem is studied over a range of fields and is sometimes termed community detection, module detection, or graph partitioning. A popular class of algorithms for module detection relies on optimizing a function of modularity to identify the structure. In practice, graphs are often learned from the data, and thus prone to uncertainty. In these settings, the uncertainty of the network structure can become exaggerated by giving unreliable estimates of the module structure. In this work, we begin to address this challenge through the use of a nonparametric bootstrap approach to assessing the stability of module detection in a graph. Estimates of stability are presented at the level of the individual node, the inferred modules, and as an overall measure of performance for module detection in a given graph. Furthermore, bootstrap stability estimates are derived for complexity parameter selection that ultimately defines a graph from data in a way that optimizes stability. This approach is utilized in connection with correlation graphs but is generalizable to other graphs that are defined through the use of dissimilarity measures. We demonstrate our approach using a broad range of simulations and on a metabolomics dataset from the Beijing Olympics Air Pollution study. These approaches are implemented using bootcluster package that is available in the R programming language.

The cholesterol autoxidation products, 7-ketocholesterol and 7ß-hydroxycholesterol are associated with serum neurofilaments in multiple sclerosis.

BACKGROUND: Serum neurofilament light chain (sNfL) is an established marker of neuroaxonal injury in multiple sclerosis (MS). OBJECTIVES: To investigate if oxysterols produced from non-enzymatic and enzymatic cholesterol oxidation are differentially associated with sNfL measurements in MS. METHODS: This longitudinal study included 62 relapsing-remitting (RR-MS) and 36 progressive MS (PMS) patients with baseline and 5-year follow-up measures of serum levels of 6 oxysterols, sNfL and lipids. The oxysterols, 24-hydroxycholesterol (24HC), 25HC, 27HC, 7αHC, 7ßHC and 7-ketocholesterol (7KC), were measured using liquid chromatography-mass spectrometry. sNfL was measured using single molecular array assay. Serum high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels were obtained from a lipid profile. RESULTS: The enzymatically produced oxysterols 24HC, 25HC, 27HC and 7αHC were not associated with sNfL. However, baseline levels of reactive oxygen species (ROS) produced oxysterols, 7KC (p = 0.032) and 7ßHC (p = 0.0025), were positively associated with sNfL levels at follow-up. Follow-up 7KC (p = 0.038) levels were also associated with follow-up sNfL levels. The associations of 7KC or 7ßHC with sNfL remained significant after adjusting for LDL-C or HDL-C. CONCLUSIONS: 7KC and 7ßHC, produced by ROS-mediated cholesterol oxidation are associated with neuroaxonal injury as assessed by sNfL in MS.

Variability of essential and non-essential trace elements in the follicular fluid of women undergoing in vitro fertilization (IVF).

Both essential and non-essential elements have been associated with female reproductive function in epidemiologic investigations, including among IVF populations. To date, most investigators have used blood or urine to assess biomarkers of exposure, with few employing ovarian follicular fluid (FF). FF may offer a more direct "snapshot" of the oocyte microenvironment than blood or urine, however previous studies report follicle-to-follicle variability in FF constituents that may contribute to exposure misclassification. Our objectives were to investigate sources of trace element variability, to estimate FF biomarker reliability among women undergoing IVF (n = 34), and to determine the minimum number of follicles required to estimate subject-specific mean concentrations. We measured As, Hg, Cd, Pb, Cu, Mn, Se, and Zn in FF samples using inductively coupled plasma tandem mass spectrometry. Inter-subject (between-women) variability contributed most of the variability in FF element concentrations, with ovarian, follicular, and analytical as smaller sources of variability. The proportion of variability attributable to sources between-follicles differed by age, body mass index (BMI), race, and cigarette smoking for Cu, Se, and Zn, by BMI and cigarette smoking for As, by primary infertility diagnosis for Hg, Cu, Se, and Zn, and by ovarian stimulation protocol for Mn and Se. Four to five individual follicles were sufficient to estimate subject-specific mean Cu, Se, and Zn concentrations, while >14 were necessary for As, Hg, Cd, Pb, and Mn. Overall, our results suggest that FF is a suitable source of biomarkers of As and Hg exposure in ovarian follicles. Although limited in size, our study offers the most comprehensive exploration of biological variation in FF trace elements to date and may provide guidance for future studies of ovarian trace element exposures.