Ainārs Stepens

Prof. Dr. Ainārs Stepens

Riga Stradiņš University, Riga, Rīga, Latvia
orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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6 March 2008 in New England Journal of Medicine
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Journal Article
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ASAinārs Stepens
Ainārs Stepens
ILInāra Logina
Ināra Logina
VLViesturs Liguts
Viesturs Liguts
PAPauls Aldiņš
Pauls Aldiņš
IEIlze Ekšteina
Ilze Ekšteina
MDMichael Donaghy
Michael Donaghy
A distinctive extrapyramidal syndrome has been observed in intravenous methcathinone (ephedrone) users in Eastern Europe and Russia.

10 December 2021 in Military Medical Research
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SSStefan Sammito
Stefan Sammito
Vedran HadžićVedran Hadžić
Vedran Hadžić
TKThomas Karakolis
Thomas Karakolis
KKKaren Kelly
Karen Kelly
SPSusan P. Proctor
Susan P. Proctor
WZWes Zimmermann
Wes Zimmermann
Background: Musculoskeletal injuries (MSkIs) are a leading cause of health care utilization, as well as limited duty and disability in the US military and other armed forces. MSkIs affect members of the military during initial training, operational training, and deployment and have a direct negative impact on overall troop readiness. Currently, a systematic overview of all risk factors for MSkIs in the military is not available. Methods: A systematic literature search was carried out using the PubMed, Ovid/Medline, and Web of Science databases from January 1, 2000 to September 10, 2019. Additionally, a reference list scan was performed (using the “snowball method”). Thereafter, an international, multidisciplinary expert panel scored the level of evidence per risk factor, and a classification of modifiable/non-modifiable was made. Results: In total, 176 original papers and 3 meta-analyses were included in the review. A list of 57 reported potential risk factors was formed. For 21 risk factors, the level of evidence was considered moderate or strong. Based on this literature review and an in-depth analysis, the expert panel developed a model to display the most relevant risk factors identified, introducing the idea of the “order of importance” and including concepts that are modifiable/non-modifiable, as well as extrinsic/intrinsic risk factors. Conclusions: This is the qualitative systematic review of studies on risk factors for MSkIs in the military that has attempted to be all-inclusive. A total of 57 different potential risk factors were identified, and a new, prioritizing injury model was developed. This model may help us to understand risk factors that can be addressed, and in which order they should be prioritized when planning intervention strategies within military groups.

29 October 2010 in Brain
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ASAinārs Stepens
Ainārs Stepens
CSCharlotte Jane Stagg
Charlotte Jane Stagg
APArdis Platkājis
Ardis Platkājis
MBMarie-Hélène Boudrias
Marie-Hélène Boudrias
HJHeidi Johansen-Berg
Heidi Johansen-Berg
MDMichael Donaghy
Michael Donaghy
We examined white matter abnormalities in patients with a distinctive extrapyramidal syndrome due to intravenous methcathinone (ephedrone) abuse. We performed diffusion tensor imaging in 10 patients and 15 age-matched controls to assess white matter structure across the whole brain. Diffuse significant decreases in white matter fractional anisotropy, a diffusion tensor imaging metric reflecting microstructural integrity, occurred in patients compared with controls. In addition, we identified two foci of severe white matter abnormality underlying the right ventral premotor cortex and the medial frontal cortex, two cortical regions involved in higher-level executive control of motor function. Paths connecting different cortical regions with the globus pallidus, the nucleus previously shown to be abnormal on structural imaging in these patients, were generated using probabilistic tractography. The fractional anisotropy within all these tracts was lower in the patient group than in controls. Finally, we tested for a relationship between white matter integrity and clinical outcome. We identified a region within the left corticospinal tract in which lower fractional anisotropy was associated with greater functional deficit, but this region did not show reduced fractional anisotropy in the overall patient group compared to controls. These patients have widespread white matter damage with greatest severity of damage underlying executive motor areas.

17 May 2013 in European Journal of Neurology
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ASAinārs Stepens
Ainārs Stepens
VGV. Groma
V. Groma
SSSandra Skuja
Sandra Skuja
APA. Platkājis
A. Platkājis
PAP. Aldiņš
P. Aldiņš
MDM. Donaghy
M. Donaghy

26 August 2020 in Frontiers in Aging Neuroscience
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KSKristine Sneidere
Kristine Sneidere
SMSara Mondini
Sara Mondini
ASAinārs Stepens
Ainārs Stepens
This review aimed to systematically summarize the possible neural correlates of cognitive reserve thus giving an insight into prospective biomarkers for the concept. A total of 44 studies were analyzed following PRISMA guidelines and four studies were included in the further analysis. The results indicated a relationship between P3b waveform and cognitive reserve, while more ambiguous outcomes were found when conducting resting-state EEG. This review indicates the first steps into assessing CR using physiological measures; however, more research is needed for deeper understanding of its underlying mechanisms.

16 December 2023 in Diagnostics
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Kalvis KaļvaKalvis Kaļva
Kalvis Kaļva
Nauris ZdanovskisNauris Zdanovskis
Nauris Zdanovskis
KSKristine Sneidere
Kristine Sneidere
AKAndrejs Kostiks
Andrejs Kostiks
GKGuntis Karelis
Guntis Karelis
ASAinārs Stepens
Ainārs Stepens
Diffusion tensor imaging (DTI) is an MRI analysis method that could help assess cognitive impairment (CI) in the ageing population more accurately. In this research, we evaluated fractional anisotropy (FA) of whole brain (WB) and corpus callosum (CC) in patients with normal cognition (NC), mild cognitive impairment (MCI), and moderate/severe cognitive impairment (SCI). In total, 41 participants were included in a cross-sectional study and divided into groups based on Montreal Cognitive Assessment (MoCA) scores (NC group, nine participants, MCI group, sixteen participants, and SCI group, sixteen participants). All participants underwent an MRI examination that included a DTI sequence. FA values between the groups were assessed by analysing FA value and age normative percentile. We did not find statistically significant differences between the groups when analysing CC FA values. Both approaches showed statistically significant differences in WB FA values between the MCI-SCI and MCI-NC groups, where the MCI group participants showed the highest mean FA and highest mean FA normative percentile results in WB.