Lower GM Research Articles

In Situ Accumulation of CaOx Crystals in C. quitensis Leaves and Its Relationship with Anatomy and Gas Exchange

The accumulation of crystal calcium oxalate (CaOx) in plants is linked to a type of stress-induced photosynthesis termed ‘alarm photosynthesis’, serving as a carbon reservoir when carbon dioxide (CO2) exchange is constrained. Colobanthus quitensis is an extremophyte found from southern Mexico to Antarctica, which thrives in high-altitude Andean regions. Growing under common garden conditions, C. quitensis from different latitudinal provenances display significant variations in CaOx crystal accumulation. This raises the following questions: are these differences maintained under natural conditions? And is the CaOx accumulation related to mesophyll conductance (gm) and net photosynthesis (AN) performed in situ? It is hypothesized that in provenances with lower gm, C. quitensis will exhibit an increase in the use of CaOx crystals, resulting in reduced crystal leaf abundance. Plants from Central Chile (33°), Patagonia (51°), and Antarctica (62°) were measured in situ and sampled to determine gas exchange and CaOx crystal accumulation, respectively. Both AN and gm decrease towards higher latitudes, correlating with increases in leaf mass area and leaf density. The crystal accumulation decreases at higher latitudes, correlating positively with AN and gm. Thus, in provenances where environmental conditions induce more xeric traits, the CO2 availability for photosynthesis decreases, making the activation of alarm photosynthesis feasible as an internal source of CO2.

Volume changes of deep brain structures in episodic migraine

AbstractBackground and PurposeGray matter (GM) volumes have previously shown variations in different regions in patients with migraine, particularly in cortical regions. This study focused on comparative volumetric assessment of deep brain structures, including GM and cerebrospinal fluid (CSF), in patients with and without migraine. Furthermore, a relationship between the measured volumes and clinical features of migraine was investigated.MethodsIn a cross‐sectional study, 30 patients with episodic migraine and 30 subjects without migraine were investigated through brain MRI. The migraine group had a mean ± standard deviation (SD) age of 39 ± 12 (77% female, 23% male), and the control group had a mean ± SD age of 40.5 ± 11 (70% female, 30% male). Groups were matched in terms of age, gender, and comorbidities. T1‐weighted images were transferred to an automated MRI analysis tool to measure the volumes of interested regions.ResultsOur results showed that GM volumes of caudate nuclei, thalami, mammillary bodies, right nucleus accumbens, and CSF volumes of lateral ventricles in migraine group were significantly higher compared to the control group. In addition, migraine was independently associated with a higher volume of caudates, thalami, mammillary bodies, and lateral ventricles but a lower volume of the third and fourth ventricles. An analysis of migraine clinical features revealed that a longer duration of migraine was associated with a lower GM volume of the right mammillary body and higher CSF volumes of lateral ventricles, and the third ventricle.ConclusionOur study supported the hypothesis that migraine is independently associated with the volumes of deep brain structures, specifically the thalamus, caudate, mammillary body, and ventricular system.

Sex modifies the associations of regional fat with cognitive functioning and AD‐related brain volumes, in Israeli middle‐aged adults at high AD risk

AbstractBackgroundHigh body mass index (BMI) has been consistently linked to poorer cognition and higher dementia risk, with different associations in males and females. However, BMI does not represent well specific fat depots. We examined in middle‐aged adults at high Alzheimer’s dementia (AD) risk, whether regional abdominal adiposity is associated with cognitive functioning and brain indices and whether sex modifies these associations.Methods204 healthy Israeli middle‐aged AD offspring (59.44 [SD = 7.60] years old, 60% females) underwent abdominal Magnetic Resonance Imaging (MRI) to quantify hepatic, pancreatic, and peripheral fat %‐visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). A broad cognitive battery defined global cognition and specific cognitive domains (episodic memory, working memory, executive functions, and language). A subsample of 142 participants had brain MRI to assess regional brain volumes (total gray matter [GM], hippocampus, and inferior, middle, and superior frontal gyrus [IFG, MFG, and SFG, respectively]). Partial correlations examined associations of regional abdominal adiposity with cognitive functioning, and brain indices, adjusting for age, sex, education, BMI, and time interval between abdominal MRI and the dependent variable. Fisher‐z transformation compared partial correlations between males and females.ResultsIn the whole sample, the only significant association was of higher hepatic fat % with lower GM volume (r = ‐264, p = 0.003), with similar associations in males and females. Only in males, higher pancreatic fat % was associated with lower global cognitive functioning (Males: r = ‐.276, p = .028; Females: r = 0.009, p = 0.93), executive functioning (Males: r = ‐0.267, p = 0.034; Females: r = 0.015, p = 0.87) and episodic memory (Males: r = ‐0.278, p = 0.027; Females: r = 0.068, p = 0.484) as well as with lower IFG volume (Males: r = ‐0.343, p = .017; Females: r = 0.117; p = 0.326). Also only in males, higher VAT% was associated with SFG volume (Males: r = .261, p = .045; Females: r = ‐0.198; p = 0.091).ConclusionIn middle‐aged males, but not in females, at high AD risk, regional abdominal adiposity, primarily pancreatic fat, was associated with lower cognitive functioning and lower AD‐related brain volumes. Results suggest sex differences in the contributions of fat to brain and cognitive aging. Since fat % is modifiable, these results may suggest that interventions to decrease distinct fats for the advancement of brain health must be sex‐specific.

Abstract 63: Age-related Changes In Gray Matter Cerebral Metabolism And Vascular Reactivity In Children

Introduction: Metabolic demand changes throughout childhood as the brain develops, peaking in the 2 nd decade of life. Cerebral blood flow (CBF) is dynamic throughout childhood, likely in response to the increased metabolic demand of brain development. Cerebrovascular reactivity (CVR) reflects the ability to further increase CBF in response to a stimulus, such as carbon dioxide (CO 2 ). We hypothesized that gray matter oxygen metabolism (GM CMRO 2 ) is increased in younger children, corresponding to higher GM CBF and lower GM CVR. Methods: CVR was calculated as the proportional change of a subject’s MRI-measured blood oxygen level dependent signal in response to an increase in end-tidal CO 2 administered by the RespirAct® RA-MR™ device. GM CMRO 2 was calculated voxel-by-voxel as the product of GM CBF (arterial spin labeling), GM oxygen extraction fraction (asymmetric spin echo), and arterial oxygen content (= Hb х (oxygen saturation)х1.34). Univariate relationships were tested using Spearman’s correlation coefficient, and corrected for multiple comparisons. Results: GM CVR, CBF, and CMRO 2 were calculated for 15 healthy participants (ages 8-19, 7 male). GM CMRO 2 was highest in young children and decreased with age (ρ=-0.68, P=0.005), as did CBF (ρ =-0.67, P=0.006). CVR was lower in young children, increasing with age (ρ=0.58, P=0.02). However, while GM CVR correlated with CBF (ρ=-0.64, P=0.01) it did not significantly associate with CMRO 2 (ρ=-0.43, P=0.114). Conclusion: Although GM CMRO 2 and CVR both have age-related changes, CVR does not directly correlate with CMRO 2 . Rather, their relationship may be moderated through other influences on CBF, as further study will investigate. Figure: Linear fits and 95% confidence intervals of subject data, including age, GM CBF, and GM CMRO 2 , versus GM CVR. P-values are from Spearman’s test for monotonic correlation.

Hypertensive Aspects of Cardiometabolic Disorders Are Associated with Lower Brain Microstructure, Perfusion, and Cognition.

Cardiometabolic disorders (hypertension, diabetes) are key modifiable risk factors for Alzheimer's disease and related disorders. They often co-occur; yet, the extent to which they independently affect brain structure and function is unclear. We hypothesized their combined effect is greater in associations with cognitive function and neuroimaging biomarkers of white matter (WM) health and cerebral perfusion in a diverse older adult cohort. Participants aged 50-85 years received: clinical evaluation, oral glucose tolerance testing, neuroimaging, cognitive testing, and adjudication. Neuroimaging included: T1 (gray [GM]/WM segmentation, regional volumes/thicknesses); FLAIR (WM hyperintensity volume [WMHv]; arterial spin labeling (cerebral blood flow); diffusion tensor imaging (fractional anisotropy [FA]); and neurite orientation dispersion and density imaging (Free Water). Hypertension (HTN) and impaired glucose tolerance (IGT) were staged and cardiometabolic status was categorized (HTN only, IGT only, IGT+HTN, neither). Multivariable linear regression modeled associations with cognitive and neuroimaging measures (covariates: age, gender, race). MRI was available for 478 participants (35% mild cognitive impairment, 10% dementia) with mean age 70±8 years, 74% with HTN, 61% with IGT, and 15% self-identified as Black/African-American. IGT+HTN was significantly associated with cognitive impairment, higher WM Free Water and WMHv, lower FA, and lower GM perfusion compared to neither factor. HTN alone was associated with poorer cognition and lower GM perfusion. Cardiometabolic factors were not associated with GM macrostructure (volumes, temporal lobe cortical thickness) or cognitive status. HTN and its co-occurrence with IGT (HTN+IGT) were associated with lower global cognitive performance and reduced GM perfusion and impaired WM microstructure.

Cerebrovascular reactivity in multiple sclerosis is restored with reduced inflammation during immunomodulation

Cerebrovascular reactivity (CVR) reflects the capacity of the brain’s vasculature to increase blood flow following a vasodilatory stimulus. Reactivity is an essential property of the brain’s blood vessels that maintains nutrient supplies in the face of changing demand. In Multiple Sclerosis (MS), CVR may be diminished with brain inflammation and this may contribute to neurodegeneration. We test the hypothesis that CVR is altered with MS neuroinflammation and that it is restored when inflammation is reduced. Using a breath-hold task during functional Magnetic Resonance Imaging (MRI), we mapped grey matter and white matter CVRs (CVRGM and CVRWM, respectively) in 23 young MS patients, eligible for disease modifying therapy, before and during Interferon beta treatment. Inflammatory activity was inferred from the presence of Gadolinium enhancing lesions at MRI. Eighteen age and gender-matched healthy controls (HC) were also assessed. Enhancing lesions were observed in 12 patients at the start of the study and in 3 patients during treatment. Patients had lower pre-treatment CVRGM (p = 0.04) and CVRWM (p = 0.02) compared to HC. In patients, a lower pre-treatment CVRGM was associated with a lower GM volume (r = 0.60, p = 0.003). On-treatment, there was an increase in CVRGM (p = 0.02) and CVRWM (p = 0.03) that negatively correlated with pre-treatment CVR (GM: r = − 0.58, p = 0.005; WM: r = − 0.60, p = 0.003). CVR increased when enhancing lesions reduced in number (GM: r = − 0.48, p = 0.02, WM: r = − 0.62, p = 0.003). Resolution of inflammation may restore altered cerebrovascular function limiting neurodegeneration in MS. Imaging of cerebrovascular function may thereby inform tissue physiology and improve treatment monitoring.

Immunogenicity and clinical efficacy of anti‐SARS‐CoV‐2 vaccination in patients with hematological malignancies: Results of a prospective cohort study of 365 patients

Immunogenicity and clinical efficacy of anti‐SARS‐CoV‐2 vaccination in patients with hematological malignancies: Results of a prospective cohort study of 365 patients

Detoxification Role of Metabolic Glutathione S-Transferase (GST) Genes in Blood Lead Concentrations of Jamaican Children with and without Autism Spectrum Disorder.

Glutathione S-transferases (GST) are involved in the detoxification of exogenous chemicals including lead (Pb). Using data from 344 pairs of autism spectrum disorder (ASD) cases and age- and sex-matched typically developing (TD) controls (2–8 years old) from Jamaica, we investigated the interaction between three GST genes and ASD status as determinants of blood Pb concentrations (BPbCs). We found that ASD cases had lower geometric mean BPbCs than TD children (1.74 vs. 2.27 µg/dL, p < 0.01). Using a co-dominant genetic model, ASD cases with the Ile/Val genotype for the GSTP1 Ile105Val polymorphism had lower GM BPbCs than TD controls, after adjusting for a known interaction between GSTP1 and GSTT1, child’s parish, socioeconomic status, consumption of lettuce, fried plantains, and canned fish (Ile/Val: 1.78 vs. 2.13 µg/dL, p = 0.03). Similarly, among carriers of the I/I or I/D (I*) genotype for GSTT1 and GSTM1, ASD cases had lower adjusted GM BPbCs than TD controls (GSTT1 I*: 1.61 vs. 1.91 µg/dL, p = 0.01; GSTM1 I*: 1.71 vs. 2.04 µg/dL, p = 0.01). Our findings suggest that genetic polymorphisms in GST genes may influence detoxification of Pb by the enzymes they encode in Jamaican children with and without ASD.

Effect of chronic alcohol consumption on brain structure in males with alcohol use disorder without a familiar history of alcoholism

Structural brain damages caused by chronic alcohol consumption have been extensively reported. However, the neuroimaging findings in people with alcohol use disorder (AUD) are relatively inconsistent. This inconsistency may be due to the influence of different variables that are not always considered, such as the presence of a family history of alcoholism (FHA). The main aim of this research is to study the gray (GM) and white matter (WM) volumes in male participants with AUD without FHA compared to healthy control males (HC) without FHA. For this study, we included 19 participants with AUD without FHA and 18 HC males without FHA. T1-weighted images were acquired with a General Electric Signa Exite 1.5 T scanner. GM and WM tissues were calculated using Diffeomorphic Anatomical Registration Through Exponentiated Lie algebra (DARTEL). All analyses were controlled for age and total brain volume. The statistical threshold was calculated with AlphaSim and further adjusted to account for the non-isotropic smoothness of structural images, according to Hayasaka et al. (2004). The obtained main results showed that, relative to the HC group, the participants with AUD without FHA had significantly lower GM in several brain structures, reflecting relatively purely the effects of chronic alcohol intake on brain volume. GM structure integrity is relevant for the efficient functioning of low and high-order cognitive processes used in everyday life, and its damage seems to be related to the severity/intensity/chronicity of the AUD. As such, it becomes relevant to assess and follow brain structural changes through the dependence course.

Structural Alteration of Medial Temporal Lobe Subfield in the Amnestic Mild Cognitive Impairment Stage of Alzheimer's Disease.

Objective Volume reduction and structural abnormality is the most replicated finding in neuroimaging studies of Alzheimer's disease (AD). Amnestic mild cognitive impairment (aMCI) is the early stage of AD development. Thus, it is necessary to investigate the link between atrophy of regions of interest (ROIs) in medial temporal lobe, the variation trend of ROI densities and volumes among patients with cognitive impairment, and the distribution characteristics of ROIs in the aMCI group, Alzheimer's disease (AD) group, and normal control (NC) group. Methods 30 patients with aMCI, 16 patients with AD, and 30 NC are recruited; magnetic resonance imaging (MRI) brain scans are conducted. Voxel-based morphometry was employed to conduct the quantitative measurement of gray matter densities of the hippocampus, amygdala, entorhinal cortex, and mammillary body (MB). FreeSurfer was utilized to automatically segment the hippocampus into 21 subregions and the amygdala into 9 subregions. Then, their subregion volumes and total volume were calculated. Finally, the ANOVA and multiple comparisons were performed on the above-mentioned data from these three groups. Results AD had lower GM densities than MCI, and MCI had lower GM densities than NC, but not all of the differences were statistically significant. In the comparisons of AD-aMCI-NC, AD-aMCI, and AD-NC, the hippocampus, amygdala, and entorhinal cortex showed differences in the gray matter densities (p < 0.05); the differences of mammillary body densities were not significant in the random comparison between these three groups (p > 0.05). The hippocampus densities and volumes of the subjects from the aMCI group and the AD group were bilaterally symmetric. The gray matter densities of the right side of the entorhinal cortex inside each group and the hippocampus from the NC group were higher than those of the left side (p < 0.05), and the gray matter densities of the amygdala and mammillary body were bilaterally symmetric in the three groups (p > 0.05). There were no gender differences of four ROIs in the AD, aMCI, and NC groups (p > 0.05). The volume differences of the hippocampus presubiculum-body and parasubiculum manifest no statistical significance (p > 0.05) in the random comparison between these three groups. Volume differences of the left amygdala basal nucleus, the left lateral nucleus, the left cortical amygdala transitional area, the left paravamnion nucleus, and bilateral hippocampal amygdala transition area (HATA) had statistical differences only between the AD group and the NC group (p < 0.05). Conclusion Structural defects of medial temporal lobe subfields were revealed in the aMCI and AD groups. Decreased gray matter densities of the hippocampus, entorhinal cortex, and amygdala could distinguish patients with early stage of AD between aMCI and NC. Volume decline of the hippocampus and amygdala subfields could only distinguish AD between NC.

Complement and NfL associations with brain structure and functional connectivity alterations in presymptomatic and symptomatic GRN mutation carriers

AbstractBackgroundProgranulin (GRN) mutations cause autosomal dominant frontotemporal lobar degeneration. Clinical trials for GRN‐targeted therapies are underway, yet reliable biomarkers to predict onset and track disease progression remain elusive. Task‐free functional MRI (tf‐fMRI) connectivity may be more sensitive than structural measures for detecting presymptomatic changes (Dopper, 2014; Premi, 2016). Presymptomatic GRN feature tf‐fMRI hyperconnectivity that is more pronounced in older carriers presumably closer to symptom onset, suggesting hyperconnectivity may be a harbinger of disease (Lee, 2019). To aid the interpretation of hyperconnectivity, we explored relationships of structural and tf‐fMRI measures with candidate fluid biomarkers for GRN: CSF complement proteins C3b and C1q, which drive neurodegeneration in GRN ‐/‐ mice (Lui, 2016) and plasma neurofilament light chain (NfL), a marker of axonal injury.MethodWe studied 20 symptomatic GRN (Sx), 39 presymptomatic GRN (preSx), and 67 healthy‐controls (HC). Cross‐sectional CSF C3b, C1q, and plasma NfL concentrations were compared between groups. Correlations controlling for age assessed relationships between fluid biomarkers and symptom severity (CDR®+NACC‐FTLD box score). Voxelwise multiple regression models examined interactions between fluid biomarkers and gene status on grey matter probability maps (GM) and voxelwise tf‐fMRI whole‐brain weighted degree (WBD) maps.ResultComplement concentrations were similar between Sx, preSx, and HC. Across all GRN, C3b concentrations increased with symptom severity (r=0.34, p=0.04). In Sx, but not preSx, higher C3b was associated with increased WBD in medial‐frontal regions, left insula, and thalamus compared to HC. Sx had higher NfL concentrations compared to preSx and HC. Across all GRN and in Sx, higher NfL was associated with greater symptom severity (r=0.60, p&lt;0.001; r=0.72, p&lt;0.001). In Sx, higher NfL was associated with lower GM in precuneus and bilateral frontoinsular cortices, but not WBD, compared to HC. In preSx, higher NfL was associated with increased WBD in thalamus and right temporal regions, but not GM, compared to HC.ConclusionC3b and NfL concentrations correlated with symptom severity. C3b concentrations were associated with tf‐fMRI connectivity alterations in Sx while NfL concentrations were associated with connectivity alterations in preSx. Longitudinal studies are needed to determine temporal relationships between altered connectivity, atrophy, complement, NfL rise, and symptom onset.

Products of an Early Cretaceous extensional mechanism in the central Great Xing'an Range: Felsic plutons in the Zhalantun area and their parental magma compositions and diagenetic processes

Late Mesozoic extensional mechanisms in the Great Xing'an Range (GXR) and relevant crust–mantle interactions are complicated, which result in widespread magmatisms with diverse parental origins and petrogenesises. In this paper, we present the lithology, whole‐rock geochemistry, and zircon U–Pb–Lu–Hf isotopes for granodiorite‐monzogranite rocks (GM) and their enclaves of quartz monzodiorites in the Zhalantun area, east of central GXR. Zircon U–Pb dating results reveal that both GM rocks and their enclaves of quartz monzodiorites yield a nearly identical crystallization age of ~125 Ma. The GM rocks exhibit weak peraluminous and high‐K calc‐alkaline compositions with high SiO2, Na2O + K2O, and Al2O3 contents, and low MgO, Mg#, Fe2O3T, and TiO2 contents, which are characterized by fractionated REE patterns, relatively strong negative Eu anomalies, enrichments of LILEs (e.g., Rb, Ba, and K), and depletions of Nb, Ta, P, and Ti. The parental origins for GM samples were juvenile crustal materials, with positive zircon εHf(t) values of +2.5 to +12.9. The whole‐rock and zircon geochemical simulations limit slightly lower GM magma crystallization temperatures (TTi‐Zrn) of 683–824°C and relatively more oxidizing conditions (log(fO2) = FMQ+7.6–FMQ‐6.8), and further confine that they were probably formed by ~10–35% degrees of fluid‐present partial melting of lower to middle crustal materials, with fractional crystallization and/or residual mineral phases of plagioclase, amphibole, clinopyroxene, and garnet. By contrast, the enclaves of quartz monzodiorites possess lower SiO2 and Na2O + K2O compositions, but higher MgO, Mg#, Fe2O3T, and TiO2 values, which are consistent with metaluminous–weak peraluminous and high‐K calc‐alkaline series. All quartz monzodiorites exhibit sub‐parallel right‐declined REE patterns, negligible to none Eu anomalies, enrichments of LILEs, and depletions of Nb, Ta, and Ti. Combined with mineral morphology and disequilibrium structures, the whole‐rock geochemical and Hf isotopic simulations imply that parental magmas for quartz monzodiorites were hybrid mixtures between ~50% host GM acid magmas and ~50% ancient crust compositions, with a wide range of zircon εHf(t) of +14.0 to −7.7, slightly higher TTi‐Zrn of 710–835°C, and lower log(fO2) of FMQ+8.2–FMQ‐10.5. Taken together, felsic plutons in the Zhalantun area correspond to an episode of extensional mechanism‐related crust–mantle interactions, which might be induced by either the Mongol‐Okhotsk domain or Palaeo‐Pacific tectonic domain, or both of them.

Microstructural Tissue Changes in Alzheimer Disease Brains: Insights from Magnetization Transfer Imaging.

Reductions in magnetization transfer ratio have been associated with brain microstructural damage. We aim to compare magnetization transfer ratio in global and regional GM and WM between individuals with Alzheimer disease and healthy control participants to analyze the relationship between magnetization transfer ratio and cognitive functioning in Alzheimer disease. In this prospective study, participants with Alzheimer disease and a group of age-matched healthy control participants underwent clinical examinations and 3T MR imaging. Magnetization transfer ratios were determined in the cortex, AD-signature regions, normal-appearing WM, and WM hyperintensities. Seventy-seven study participants (mean age ± SD, 72 ± 8 years; 47 female) and 77 age-matched healthy control participants (mean age ± SD, 72 ± 8 years; 44 female) were evaluated. Magnetization transfer ratio values were lower in patients with Alzheimer disease than in healthy control participants in all investigated regions. When adjusting for atrophy and extent of WM hyperintensities, significant differences were seen in the global cortex (OR = 0.47; 95% CI: 0.22, 0.97; P = .04), in Alzheimer disease-signature regions (OR = 0.31; 95% CI: 0.14, 0.67; P = .003), in normal-appearing WM (OR = 0.59; 95% CI: 0.39, 0.88; P = .01), and in WM hyperintensities (OR = 0.18; 95% CI: 0.09, 0.33; P ≤ .001). The magnetization transfer ratio in these regions was an independent determinant of AD. When correcting for atrophy and WM hyperintensity extent, lower GM magnetization transfer ratios were associated with poorer global cognition, language function, and constructional praxis. Alzheimer disease is associated with magnetization transfer ratio reductions in GM and WM regions of the brain. Lower magnetization transfer ratios in the entire cortex and AD-signature regions contribute to cognitive impairment independent of brain atrophy and WM damage.

Cortical volume reductions as a sign of secondary cerebral and cerebellar impairment in patients with degenerative cervical myelopathy

This study investigated supra- and infratentorial structural gray and white matter (GM, WM) alterations in patients with degenerative cervical myelopathy (DCM) as an indicator of secondary harm due to chronic cervical cord compression and micro trauma. With MRI-based anatomical assessment and subsequent voxel-based morphometry analyses, pre- and postoperative volume alterations in the primary motor cortex (MI), the primary somatosensory cortex (SI), the supplementary motor area (SMA), and the cerebellum were analyzed in 43 DCM patients and 20 controls. We assessed disease-related symptom severity by the modified Japanese Orthopaedic Association scale (mJOA). The study also explored symptom severity-based brain volume alterations as well as their association with clinical status. Patients had lower mJOA scores (p = .000) and lower GM volume than controls in SI (p = .016) and cerebellar regions (p = .001). Symptom severity-based subgroup analyses revealed volume reductions in almost all investigated GM ROIs (MI: p = .001; CB: p = .040; SMA: p = .007) in patients with severe clinical symptoms as well as atrophy already present in patients with moderate symptom severity. Clinical symptoms in DCM were associated with cortical and cerebellar volume reduction. GM volume alterations may serve as an indicator of both disease severity and ongoing disease progression in DCM, and should be considered in further patient care and treatment monitoring.

Herd-level associations between somatic cell counts and economic performance indicators in Brazilian dairy herds

The aims of the present study were to provide a portrait of the techno-economic status of dairy herds in Minas Gerais, Brazil, particularly with respect to bulk-tank somatic cell count (BTSCC) data, and to examine the herd-level associations of BTSCC with various economic performance indicators (EPI). Data from 543 herds, 1,052 herd-year records in total, spread over 3 years (2015-2017), from the South and Southwest mesoregions of Minas Gerais State were provided by the Brazilian Support Agency to Micro and Small Companies Division Minas Gerais (SEBRAE). Herds had an average of 82 lactating cows per herd, milk yield of 17 L/cow per day, and availability of financial information via routine monthly economic surveys. The EPI data (revenue, gross margin, GM; net margin, NM; profit; break-even point; and operational profitability) of each herd was measured monthly by SEBRAE personnel, and herd-year averages of all variables were computed. Bulk-tank data (SCC, total bacterial count, content of crude protein and fat) taken by producers or dairy processors were recorded by SEBRAE personal; and corresponding herd-year averages were calculated and included in the SEBRAE database. There were 209 selected herds, which passed all edit checks, and which had data for all 3 years. The EPI (all expressed on a per-cow basis, $/cow per year) were analyzed, including the effects of region, year, log (ln) BTSCC, production level, and herd size, together with the random effect of herd nested within region. A high proportion of herds (94.6%) presented data records (herd-years) with an average BTSCC > 200 × 103 cells/mL: 37.8% of herd-year records had BTSCC between >200 and ≤400, 14.5% with BTSCC between >400 and ≤500, 25% with BTSCC between >500 and ≤750, and 17.3% with BTSCC >750. For each unit increase in ln BTSCC, revenue declined by $228.5/cow per year, GM by $155.6/cow per year, and profit by $138.6/cow per year. Herds with cows of lower production (<14 kg/d) presented lower GM ($286.8/cow per year) compared with herds containing cows producing ≥14 kg/d (≥14 and <19 kg/d = $446.5, and ≥19 kg/d = $601.9). The small-scale milk producers (<39 lactating cows) presented lower revenue ($1,914.9/cow per year) and GM ($274.5/cow per year) and consequently a negative profit (-$224.1/cow per year) compared with other herd size categories (≥39 lactating cows). The reduction in milk yield was 641 L/cow per lactation for each unit increase in ln BTSCC; this represented 9.4% of the milk yield per lactation, assuming an average milk production of 6,843.3 L/cow per lactation of cows from herds that had BTSCC ≤ 200 × 103 cells/mL. Consequently, we found a negative association of BTSCC with profit; profit declining from $227.0 to -53.1/cow per year when the BTSCC increased from 100 to 750 × 103 cell/mL. In short, the lower the BTSCC, the greater the revenue, GM and NM, profit, and operational profitability of the herds. The reduction of milk yield was the main factor associated with higher BTSCC.

QOL-07. CORTICAL VOLUME AND THICKNESS IN ADULT SURVIVORS OF CHILDHOOD POSTERIOR FOSSA TUMORS

PURPOSEA brain tumor treatment including cranial radiotherapy has previously been associated with long-term neurocognitive sequelae. Since underlying neurological mechanisms remain inconclusive, we investigated cortical features in childhood posterior fossa tumor survivors.METHODST1-weighted MRI (MPRAGE, resolution=.98x.98x1.2mm) was acquired to investigate the cortical structure in adult survivors of childhood infratentorial tumors (n=19, 15males) (16.4–34.8 years old, >2years after treatment). These scans were compared to age- and gender- matched controls. Supratentorial cortical volume and thickness were investigated using voxel-based morphometry (VBM) and surface-based morphometry (SBM), respectively. We compared patients and controls, irradiated (n=13) versus non-irradiated patients, and investigated the age at radiotherapy (peak level: p<.001).RESULTSLower GM volumes were encountered in multiple brain areas of patients compared to controls, with the largest clusters in the right and left occipital fusiform gyri. Irradiated patients showed lower GM volumes then non-irradiated patients in the superior and middle frontal gyri, the right supramarginal gyrus and precuneus. Age at radiotherapy was associated with GM volume in the inferior frontal gyrus. SBM yielded larger cortical thickness in patients in the left precuneus, inferior temporal and fusiform gyrus. The opposite effect was only marginally significant, in the left temporal lingual gyrus. Age at radiotherapy was not associated with cortical thickness, but radiotherapy was associated with lower thickness of the left pars opercularis.CONCLUSIONWidespread differences in cortical volumes and thickness were observed in posterior fossa tumor survivors. Both radiotherapy and age at radiotherapy could be suggested as risk factors for long-term cortical development.

Higher Body-Mass Index and Lower Gray Matter Volumes in First Episode of Psychosis.

BackgroundNeurostructural alterations are often reported in first episode of psychosis (FEP), but there is heterogeneity in the direction and location of findings between individual studies. The reasons for this heterogeneity remain unknown. Obesity is disproportionately frequent already early in the course of psychosis and is associated with smaller brain volumes. Thus, we hypothesized that obesity may contribute to brain changes in FEP.MethodWe analyzed MRI scans from 120 participants with FEP and 114 healthy participants. In primary analyses, we performed voxel-based morphometry (VBM) with small volume corrections to regions associated with FEP or obesity in previous meta-analyses. In secondary analyses, we performed whole-brain VBM analyses.ResultsIn primary analyses, we found that when controlling for BMI, FEP had lower GM volume than healthy participants in a) left fronto-temporal region (pTFCE = 0.008) and b) left postcentral gyrus (pTFCE = 0.043). When controlling for FEP, BMI was associated with lower GM volume in left cerebellum (pTFCE < 0.001). In secondary analyses, we found that when controlling for BMI, FEP had lower GM volume than healthy participants in the a) cerebellum (pTFCE = 0.004), b) left frontal (pTFCE = 0.024), and c) right temporal cortex (pTFCE = 0.031). When controlling for FEP, BMI was associated with lower GM volume in cerebellum (pTFCE = 0.004). Levels of C-reactive protein, HDL and LDL-cholesterol correlated with obesity related neurostructural alterations.ConclusionsThis study suggests that higher BMI, which is frequent in FEP, may contribute to cerebellar alterations in schizophrenia. As previous studies showed that obesity-related brain alterations may be reversible, our findings raise the possibility that improving the screening for and treatment of obesity and associated metabolic changes could preserve brain structure in FEP.

GM 및 종경사 변경에 따른 선박의 조종성능변화에 관한 실험적 연구

The aim of this study was to investigate the manoeuvrability of a ship in different Center of Gravity (CG) conditions. Free Running Model Tests (FRMT), such as 35°turning circle tests, 20/20 zigzag manoeuvring tests, and 10/10 zigzag manoeuvring tests, were conducted in three GM and three trim conditions with 1/65.83 scaled KRISO Container Ship (KCS). The test results indicated that KCS in the lower GM condition and the trim by bow condition showed reduced advance and tactical diameter in turning circle tests and increased overshoot angles in zigzag tests, and those manoeuvring indices were strongly related with roll angle. In addition, sensitivity indices for three-axis CG position were suggested with prior research, and it showed that y-axis CG position significantly affected manoeuvrability of KCS due to the low GM. Therefore, in the case of KCS, it is evident that the roll angle during manoeuvre is closely related with manoeuvring indices.

Reliability assessment of tissue classification algorithms for multi-center and multi-scanner data

BackgroundGray and white matter volume difference and change are important imaging markers of pathology and disease progression in neurology and psychiatry. Such measures are usually estimated from tissue segmentation maps produced by publicly available image processing pipelines. However, the reliability of the produced segmentations when using multi-center and multi-scanner data remains understudied. Here, we assess the robustness of six publicly available tissue classification pipelines across images acquired from different MR scanners and sites. MethodsWe used 90 T1-weighted images of a single individual, scanned in 73 sessions across 27 different sites to assess the robustness of the tissue classification tools. Variability in Dice similarity index values and tissue volumes was assessed for Atropos, BISON, Classify_Clean, FAST, FreeSurfer, and SPM12. ResultsBISON had the highest overall Dice coefficient for GM, followed by SPM12 and Atropos; while Atropos had the highest overall Dice coefficient for WM, followed by BISON and SPM12. BISON had the lowest overall variability in its volumetric estimates, followed by FreeSurfer, and SPM12. All methods also had significant differences between some of their estimates across different scanner manufacturers (e.g. BISON had significantly higher GM estimates and correspondingly lower WM estimates for GE scans compared to Philips and Siemens), and different signal-to-noise ratio (SNR) levels (e.g. FAST and FreeSurfer had significantly higher WM volume estimates for high versus medium and low SNR tertiles as well as correspondingly lower GM volume estimates). ConclusionsOur comparisons provide a benchmark on the reliability of the publicly used tissue classification techniques and the amount of variability that can be expected when using large multi-center and multi-scanner databases.

Effects of soil nitrogen (N) deficiency on photosynthetic N-use efficiency in N-fixing and non-N-fixing tree seedlings in subtropical China

Soil nitrogen (N) deficiencies can affect the photosynthetic N-use efficiency (PNUE), mesophyll conductance (gm), and leaf N allocation. However, lack of information about how these physiological characteristics in N-fixing trees could be affected by soil N deficiency and the difference between N-fixing and non-N-fixing trees. In this study, we chose seedlings of two N-fixing (Dalbergia odorifera and Erythrophleum fordii) and two non-N-fixing trees (Castanopsis hystrix and Betula alnoides) as study objects, and we conducted a pot experiment with three levels of soil N treatments (high nitrogen, set as Control; medium nitrogen, MN; and low nitrogen, LN). Our results showed that soil N deficiency significantly decreased the leaf N concentration and photosynthesis ability of the two non-N-fixing trees, but it had less influence on two N-fixing trees. The LN treatment had lower gm in D. odorifera and lower leaf N allocated to Rubisco (PR), leaf N allocated to bioenergetics (PB), and gm in B. alnoides, eventually resulting in low PNUE values. Our findings suggested that the D. odorifera and E. fordii seedlings could grow well in N-deficient soil, and adding N may increase the growth rates of B. alnoides and C. hystrix seedlings and promote the growth of artificial forests.