Biology subjects

Shulist, S. J.

Publications and source records attributed to Shulist, S. J..

3 recordsLinked to original sources

bioRxiv2023

Infant Left Amygdala Volume Is Negatively Associated with Fecal Microbiota Diversity

IntroductionRodent studies have addressed the importance of early life gut microbiota in the development of emotional and social functioning. Studies in human infants are still scarce, but associations with cognition and temperament have been reported. Neuroimaging studies have linked the amygdala with fecal microbiota diversity in infants, but crucially these studies have not covered the neonatal period, and the current study addressed this gap. MethodsThe study population included 65 infants drawn from the ongoing, general population based FinnBrain Birth Cohort Study. Brain MRI was performed around the age of one month (mean age 25 days). Fecal microbiota profiles (mean 68 days) were assessed by 16s rRNA amplicon sequencing at the age of 2.5 months. ResultsWe found a negative association between infant left amygdala volume and alpha diversity (n=52, beta =-0.0043, p=0.034, adjusted for infant sex, breastfeeding, delivery mode, age during fecal sampling, age from conception during scan, and intracranial volume, Fig.1). Amygdala volumes were not associated with beta diversity (p=0.21), nor with the abundances of individual genera when adjusted for the same covariates and multiple testing. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=112 SRC="FIGDIR/small/537273v1_fig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@bf1304org.highwire.dtl.DTLVardef@798edeorg.highwire.dtl.DTLVardef@92c040org.highwire.dtl.DTLVardef@8bc2a9_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOFigure. 1.C_FLOATNO Gut microbiota alpha diversity associates negatively with left (A), but not with right (B) amygdala volume. The grey areas depict 95% confidence intervals. C_FIG ConclusionOur results provide first evidence for associations between the brain and fecal microbiota in human neonates. Although the reported data do not allow investigation of underlying mechanisms, i.e. about the directionality of the hypothesized gut-brain connection, the reported connection encourages for future investigations of manifestations of gut-brain axis in early life.

neuroscience↗

bioRxiv2023

Effect of number of diffusion encoding directions in Neonatal Diffusion Tensor Imaging using Tract-Based Spatial Statistical analysis

Diffusion Tensor Imaging (DTI) has been used to study the developing brain in early childhood, infants and in utero studies. In infants, number of used diffusion encoding directions has traditionally been smaller in earlier studies down to the minimum of 6 orthogonal directions. While the more recent studies often involve more directions, number of used directions remains an issue when acquisition time is optimized without compromising on data quality and in retrospective studies. Variability in the number of used directions may introduce bias and uncertainties to the DTI scalar estimates that affect cross-sectional and longitudinal study of the brain. We analyzed DTI images of 133 neonates, each data having 54 directions after quality control, to evaluate the effect of number of diffusion weighting directions from 6 to 54 with interval of 6 to the DTI scalars with Tract-based spatial statistics (TBSS) analysis. The TBSS analysis was applied to DTI scalar maps, and the mean Region of Interest (ROI) values were extracted using JHU atlas. We found significant bias in ROI mean values when only 6 directions were used (positive in FA, negative in MD, AD, RD), while when using 24 directions and above, the difference to scalar values calculated from 54 direction DTI was negligible. Using DTI measurements from data with at least 24 directions may be used in comparisons with DTI measurements from data with higher numbers of directions.

neuroscience↗

bioRxiv2023

Sex differences, asymmetry and age-related white matter development in infants and 5-year-olds as assessed with Tract-Based Spatial Statistics

The rapid white matter (WM) maturation of first years of life is followed by slower yet long-lasting development, accompanied by learning of more elaborate skills. By the age of five years, behavioural and cognitive differences between females and males, and functions associated with brain lateralization such as language skills are appearing. Diffusion tensor imaging (DTI) can be used to quantify fractional anisotropy (FA) within the WM and increasing values correspond to advancing brain development. To investigate the normal features of WM development during early childhood, we gathered a DTI data set of 166 healthy infants (mean 3.8 wk, range 2-5wk; 89 males; born on gestational week 36 or later) and 144 healthy children (mean 5.4 years, range 5.1-5.8 years; 76 males). The sex differences, lateralization patterns and age-dependent changes were examined using tractbased spatial statistics (TBSS). In 5-year-olds, females showed higher FA in wide-spread regions in the posterior and the temporal WM and more so in the right hemisphere, while sex differences were not detected in infants. Gestational age showed stronger association with FA values compared to age after birth in infants. Additionally, child age at scan associated positively with FA around the age of 5 years in the body of corpus callosum, the connections of which are important especially for sensory and motor functions. Lastly, asymmetry of WM microstructure was detected already in infants, yet significant changes in lateralization pattern seems to occur during early childhood, and in 5-year-olds the pattern already resembles adult-like WM asymmetry. HighlightsO_LIWhite matter tract integrity shows widespread sex differences at the age of 5 years. C_LIO_LIWhite matter structure is highly lateralized during early childhood, and changes in asymmetry occur between the birth and 5 years of age. C_LIO_LIThe white matter lateralization pattern of 5-year-olds, unlike of infants, resembles asymmetry observed in adults. C_LI

neuroscience↗