7 research outputs found
Saliva microRNA Biomarkers of Cumulative Concussion
Recurrent concussions increase risk for persistent post-concussion symptoms, and may lead to chronic neurocognitive deficits. Little is known about the molecular pathways that contribute to persistent concussion symptoms. We hypothesized that salivary measurement of microribonucleic acids (miRNAs), a class of epitranscriptional molecules implicated in concussion pathophysiology, would provide insights about the molecular cascade resulting from recurrent concussions. This hypothesis was tested in a case-control study involving 13 former professional football athletes with a history of recurrent concussion, and 18 age/sex-matched peers. Molecules of interest were further validated in a cross-sectional study of 310 younger individuals with a history of no concussion (n = 230), a single concussion (n = 56), or recurrent concussions (n = 24). There was no difference in neurocognitive performance between the former professional athletes and their peers, or among younger individuals with varying concussion exposures. However, younger individuals without prior concussion outperformed peers with prior concussion on three balance assessments. Twenty salivary miRNAs differed (adj. p \u3c 0.05) between former professional athletes and their peers. Two of these (miR-28-3p and miR-339-3p) demonstrated relationships (p \u3c 0.05) with the number of prior concussions reported by younger individuals. miR-28-3p and miR-339-5p may play a role in the pathophysiologic mechanism involved in cumulative concussion effects
Refinement of Saliva MicroRNA Biomarkers for Sports-Related Concussion
Purpose
Recognizing sport-related concussion (SRC) is challenging and relies heavily on subjective symptom reports. An objective, biological marker could improve recognition and understanding of SRC. There is emerging evidence that salivary micro-ribonucleic acids (miRNAs) may serve as biomarkers of concussion; however, it remains unclear whether concussion-related miRNAs are impacted by exercise. We sought to determine whether 40 miRNAs previously implicated in concussion pathophysiology were affected by participation in a variety of contact and non-contact sports. Our goal was to refine a miRNA-based tool capable of identifying athletes with SRC without the confounding effects of exercise.
Methods
This case-control study harmonized data from concussed and non-concussed athletes recruited across 10 sites. Levels of salivary miRNAs within 455 samples from 314 individuals were measured with RNA sequencing. Within-subjects testing was used to identify and exclude miRNAs that changed with either: (a) a single episode of exercise (166 samples from 83 individuals) or (b) season-long participation in contact sports (212 samples from 106 individuals). The miRNAs that were not impacted by exercise were interrogated for SRC diagnostic utility using logistic regression (172 samples from 75 concussed and 97 non-concussed individuals).
Results
Two miRNAs (miR-532-5p, miR-182-5p) decreased (adjusted p \u3c 0.05) after a single episode of exercise, and 1 miRNA (miR-4510) increased only after contact sports participation. Twenty-three miRNAs changed at the end of a contact sports season. Two of these miRNAs (miR-26b-3p, miR-29c-3p) were associated (R \u3e 0.5; adjusted p \u3c 0.05) with the number of head impacts sustained in a single football practice. Among the 15 miRNAs not confounded by exercise or season-long contact sports participation, 11 demonstrated a significant difference (adjusted p \u3c 0.05) between concussed and non-concussed participants, and 6 displayed moderate ability (AUC \u3e 0.70) to identify concussion. A single ratio (miR-27a-5p/miR-30a-3p) displayed the highest accuracy (AUCâŻ=âŻ0.810, sensitivityâŻ=âŻ82.4%, specificityâŻ=âŻ73.3%) for differentiating concussed and non-concussed participants. Accuracy did not differ between participants with SRC and non-SRC (zâŻ=âŻ0.5, pâŻ=âŻ0.60).
Conclusion
Salivary miRNA levels may accurately identify SRC when not confounded by exercise. Refinement of this approach in a large cohort of athletes could eventually lead to a non-invasive, sideline adjunct for SRC assessment
Diagnosing Mild Traumatic Brain Injury Using Saliva RNA Compared to Cognitive and Balance Testing
BACKGROUND: Early, accurate diagnosis of mild traumatic brain injury (mTBI) can improve clinical outcomes for patients, but mTBI remains difficult to diagnose because of reliance on subjective symptom reports. An objective biomarker could increase diagnostic accuracy and improve clinical outcomes. The aim of this study was to assess the ability of salivary noncoding RNA (ncRNA) to serve as a diagnostic adjunct to current clinical tools. We hypothesized that saliva ncRNA levels would demonstrate comparable accuracy for identifying mTBI as measures of symptom burden, neurocognition, and balance.
METHODS: This caseâcontrol study involved 538 individuals. Participants included 251 individuals with mTBI, enrolled â€14 days postinjury, from 11 clinical sites. Saliva samples (n = 679) were collected at five time points (â€3, 4â7, 8â14, 15â30, and 31â60 days postâmTBI). Levels of ncRNAs (microRNAs, small nucleolar RNAs, and piwiâinteracting RNAs) were quantified within each sample using RNA sequencing. The first sample from each mTBI participant was compared to saliva samples from 287 controls. Samples were divided into testing (n = 430; mTBI = 201 and control = 239) and training sets (n = 108; mTBI = 50 and control = 58). The test set was used to identify ncRNA diagnostic candidates and create a diagnostic model. Model accuracy was assessed in the naĂŻve test set.
RESULTS: A model utilizing seven ncRNA ratios, along with participant age and chronic headache status, differentiated mTBI and control participants with a crossâvalidated area under the curve (AUC) of .857 in the training set (95% CI, .816â.903) and .823 in the naĂŻve test set. In a subset of participants (n = 321; mTBI = 176 and control = 145) assessed for symptom burden (PostâConcussion Symptom Scale), as well as neurocognition and balance (ClearEdge System), these clinical measures yielded crossâvalidated AUC of .835 (95% CI, .782â.880) and .853 (95% CI, .803â.899), respectively. A model employing symptom burden and four neurocognitive measures identified mTBI participants with similar AUC (.888; CI, .845â.925) as symptom burden and four ncRNAs (.932; 95% CI, .890â.965).
CONCLUSION: Salivary ncRNA levels represent a noninvasive, biologic measure that can aid objective, accurate diagnosis of mTBI
Effects of Elevated Tropospheric Ozone on the Growth, Biomass Accumulation, and Crown Architecture of Populus Tremuloides Michx
Déclin de la végétation aquatique submergée au lac Saint-Pierre de 2002 à 2021
La vĂ©gĂ©tation aquatique submergĂ©e (VAS) joue plusieurs rĂŽles Ă©cologiques cruciaux et offre des services Ă©cosystĂ©miques inestimables aux sociĂ©tĂ©s humaines. Cependant, une tendance mondiale montre un dĂ©clin de la VAS, gĂ©nĂ©ralement causĂ© par la hausse des matiĂšres en suspension et des nutriments dans lâeau. LâĂ©tude de la VAS du lac Saint-Pierre de 2002 Ă 2021 a permis de documenter lâoccurrence et la composition en espĂšces de cette vĂ©gĂ©tation. La probabilitĂ© dâobserver de la VAS aux diffĂ©rentes stations dâĂ©chantillonnage est passĂ©e de 75 % en 2002 Ă 20 % en 2021. Ce dĂ©clin de la VAS est accompagnĂ© dâun changement de composition de la communautĂ© vĂ©gĂ©tale principalement attribuable Ă la diminution de la vallisnĂ©rie dâAmĂ©rique (Vallisneria americana). Un potentiel refuge photique associĂ© Ă la masse dâeau translucide des Grands Lacs supporterait le dĂ©veloppement de la VAS dans le lac Saint-Pierre. Toute intervention rĂ©duisant la dispersion de cette masse dâeau dans le lac Saint-Pierre devrait ĂȘtre Ă©vitĂ©e. Des actions de gestion visant lâamĂ©lioration de la qualitĂ© de lâeau du lac Saint-Pierre et ses tributaires, en rĂ©duisant notamment la turbiditĂ©, sont nĂ©cessaires afin de protĂ©ger et de restaurer cette rĂ©serve mondiale de la biosphĂšre de lâUNESCO.Submerged aquatic vegetation (SAV) plays several crucial ecological roles and provides invaluable ecosystem services to humans. However, it is declining globally, principally due to an increase in the amount of suspended matter and nutrients within water bodies. A series of studies of the SAV in Lake Saint-Pierre (QuĂ©bec, Canada) conducted between 2002 and 2021, documented changes in the occurrence and species composition of this vegetation type. The probability of observing SAV at the different sampling stations decreased from 75% in 2002 to 20% in 2021. This decline was accompanied by a change in species composition, mainly associated with a decrease in the amount of American eelgrass (Vallisneria americana). The clearer mass of water flowing from the Great Lakes possibly offers a photic refuge for SAV in Lake Saint-Pierre. Any intervention that would potentially reduce the dispersion of this water mass within the lake should be avoided. Management actions aimed at improving the water quality of Lake Saint-Pierre and its tributaries, notably by reducing turbidity, are needed to restore and protect this UNESCO World Biosphere Reserve
Freshwater Crayfish: A Potential Benthic-Zone Indicator of Nanosilver and Ionic Silver Pollution
Nowadays,
silver nanoparticles (AgNPs) are utilized in numerous
applications, raising justified concerns about their release into
the environment. This study demonstrates the potential to use freshwater
crayfish as a benthic-zone indicator of nanosilver and ionic silver
pollution. Crayfish were acclimated to 20 L aquaria filled with Hudson
River water (HRW) and exposed for 14 days to widely used Creighton
AgNPs and Ag<sup>+</sup> at doses of up to 360 ÎŒg L<sup>â1</sup> to surpass regulated water concentrations. The uptake and distribution
of Ag in over 650 exoskeletons, gills, hepatopancreas and muscles
samples were determined by inductively coupled plasma optical emission
spectroscopy (ICP-OES) in conjunction with two complementary U.S.
EPA-endorsed methods: the external calibration and the standard additions.
Reflecting the environmental plasticity of the two investigated species, <i>Orconectes virilis</i> accumulated in a dose-dependent manner
more Ag than <i>Procambarus clarkii</i> (on average 31%
more Ag). Both species showed DNA damage and severe histological changes
in the presence of Ag. However, Ag<sup>+</sup> generally led to higher
Ag accumulations (28%) and was more toxic. By the harvest day, about
14 ± 9% of the 360 ÎŒg L<sup>â1</sup> of AgNP exposure
in the HRW oxidized to Ag<sup>+</sup> and may have contributed to
the observed toxicities and bioaccumulations. The hepatopancreas (1.5â17.4
ÎŒg of Ag g<sup>â1</sup> of tissue) was identified as
the best tissue-indicator of AgNP pollution, while the gills (4.5â22.0
ÎŒg g<sup>â1</sup>) and hepatopancreas (2.5â16.7
ÎŒg g<sup>â1</sup>) complementarily monitored the presence
of Ag<sup>+</sup>