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Cerebrospinal fluid (CSF) biomarkers T-Tau and Aβ(42) are linked with Alzheimer's disease (AD), yet little is known about the relationship between CSF biomarkers and structural brain alteration in healthy adults. In this study we examined the extent to which AD biomarkers measured in CSF predict brain microstructure indexed by diffusion tensor imaging (DTI) and volume indexed by T1-weighted imaging. Forty-three middle-aged adults with parental family history of AD received baseline lumbar puncture and MRI approximately 3.5 years later. Voxel-wise image analysis methods were used to test whether baseline CSF Aβ(42), total tau (T-Tau), phosphorylated tau (P-Tau) and neurofilament light protein predicted brain microstructure as indexed by DTI and gray matter volume indexed by T1-weighted imaging. T-Tau and T-Tau/Aβ(42) were widely correlated with indices of brain microstructure (mean, axial, and radial diffusivity), notably in white matter regions adjacent to gray matter structures affected in the earliest stages of AD. None of the CSF biomarkers were related to gray matter volume. Elevated P-Tau and P-Tau/Aβ(42) levels were associated with lower recognition performance on the Rey Auditory Verbal Learning Test. Overall, the results suggest that CSF biomarkers are related to brain microstructure in healthy adults with elevated risk of developing AD. Furthermore, the results clearly suggest that early pathological changes in AD can be detected with DTI and occur not only in cortex, but also in white matter.

Objective: Black populations show increased incidences of diagnosis, worse disease severity, and earlier likelihood of mortality due to MS. Clinical outcomes are also linked to biological sex and as with Black individuals, MS characteristics between sexes have also shifted overtime. This study examined whether clinical disease progression differed by race and sex for patients with MS., Design: "Black" (N = 47) and "White" (N = 58) participants with MS (82 % female) were recruited from a longitudinal examination of the impact of race and sex on the cognition and disease duration of patients in the gulf south region of the United States., Results: Black participants had shorter disease durations [F (1,103) = 4.70, p = .03], (MDiff = [-3.96]) and were younger [F (1, 103) = 14.25, p < .001], (MDiff = [-9.04]). Despite this, Black individuals had worse SDMT t-scores [F (1, 103) = 5.22, p = .024], (MDiff = [-4.62])]. Women exhibited higher MSSS scores [F (1, 96) = 5.59, p = .02], (MDiff = [-2.15]). Specifically, Black women were younger than White women [F (1, 84) = 14.47, p < .001], (MDiff = [-9.15])] and had shorter disease durations [F (1, 84) = 6.04, p = .016], (MDiff = [-4.57])] yet scored lower on the SDMT T-scores [F (1, 84) = 6.11, p = .015], (MDiff = [-5.51])]., Conclusion: Findings suggest an interaction between race and sex may influence clinical progression in MS. Despite being younger and having shorter disease durations Black participants with MS, specifically Black women exhibited worse clinical outcomes., Summary: For women and men, MS incidence among Black Americans has become similar to White Americans. However, Black individuals experience greater disease severity and earlier mortality. Clinical impairment often accompanies MS. We examined the influence of race and sex on clinical status using the Symbol Digit Modalities Test t-scores (SDMT T-scores) and Multiple Sclerosis Severity Scores (MSSS) in Black (N = 47) and White (N = 58) patients with MS. Women exhibited higher MSSS scores than men [F (1, 96) = 5.59, p = .02], (MDiff = [-2.15]). Black participants had shorter disease durations [F (1, 103) = 4.70, p = .03], (MDiff = [-3.96]) and were younger [F (1, 103) = 14.25, p < .001], (MDiff = [-9.04]). Despite this, Black individuals had worse SDMT T-scores [F (1, 103) = 5.22, p = .024], (MDiff = [-4.62])]. Specifically, Black women were younger than White women [F (1, 84) = 14.47, p < .001], (MDiff = [-9.15])] and had shorter disease durations [F (1, 84) = 6.04, p = .016], (MDiff = [-4.57])] yet scored lower on the SDMT T-scores [F (1, 84) = 6.11, p = .015], (MDiff = [-5.51])]. These findings suggest that an interaction between race and sex may influence clinical progression in MS., Competing Interests: Declaration of competing interest The authors have no competing interest nor relevant financial or non-financial interests to disclose., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The biomarker cortisol assesses the impact of biopsychosocial stressors that activate the stress response system. Hair has emerged as a valid and non-invasive means of gauging cumulative cortisol deposited over month-long periods of time. Established protocols for the extraction of hair cortisol are being validated and refined in humans, yet methodological information about hair characteristics on cortisol remains limited. In addition to external hair exposures (e.g. dye, time spent outside), we examined hair categorization or type (e.g. kinky, straight) by extending a hair typing methodology for scientific use that is currently popular among hair care professionals. We then examined the interaction between hair type and race on cortisol levels with a hair questionnaire. Three studies were pooled to investigate how sample weight, hair type, race, heat exposures, and hair treatments impacted cumulative hair cortisol concentrations. Study 1 consisted of Adult Kenyan Medical Workers (N = 44); Study 2 Mexican and Mexican Americans (N = 106); and Study 3 American Youth (N = 107). We found significantly higher cortisol in 5 mg of hair when compared to larger sample weights, and higher cortisol in those who spent more time outdoors. Cortisol concentrations differed between racial groups and varied by hair type; moreover, there were directional differences in cumulative cortisol from straighter to curlier hair types which depended on racial group. In addition to demonstrating the impact of relatively novel control factors like hair sample weight, outdoor exposure, and hair type, the present study illustrates the importance of disentangling hair type and race to understand variability in cumulative hair cortisol. These influences should be included in future studies that measure hair cortisol., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

A high percent of oxidative energy metabolism is needed to support brain growth during infancy. Unhealthy diets and limited nutrition, as well as other environmental insults, can compromise these essential developmental processes. In particular, iron deficiency anemia (IDA) has been found to undermine both normal brain growth and neurobehavioral development. Even moderate ID may affect neural maturation because when iron is limited, it is prioritized first to red blood cells over the brain. A primate model was used to investigate the neural effects of a transient ID and if deficits would persist after iron treatment. The large size and postnatal growth of the monkey brain makes the findings relevant to the metabolic and iron needs of human infants, and initiating treatment upon diagnosis of anemia reflects clinical practice. Specifically, this analysis determined whether brain maturation would still be compromised at 1 year of age if an anemic infant was treated promptly once diagnosed. The hematology and iron status of 41 infant rhesus monkeys was screened at 2-month intervals. Fifteen became ID; 12 met clinical criteria for anemia and were administered iron dextran and B vitamins for 1-2 months. MRI scans were acquired at 1 year. The volumetric and diffusion tensor imaging (DTI) measures from the ID infants were compared with monkeys who remained continuously iron sufficient (IS). A prior history of ID was associated with smaller total brain volumes, driven primarily by significantly less total gray matter (GM) and smaller GM volumes in several cortical regions. At the macrostructual level, the effect on white matter volumes (WM) was not as overt. However, DTI analyses of WM microstructure indicated two later-maturating anterior tracts were negatively affected. The findings reaffirm the importance of iron for normal brain development. Given that brain differences were still evident even after iron treatment and following recovery of iron-dependent hematological indices, the results highlight the importance of early detection and preemptive supplementation to limit the neural consequences of ID., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Vlasova, Wang, Willette, Styner, Lubach, Kling, Georgieff, Rao and Coe.)

Recent studies suggest that white matter abnormalities contribute to both motor and non-motor symptoms of Parkinson’s disease. The present study was designed to investigate the degree to which diffusion tensor magnetic resonance imaging (DTI) indices are related to executive function in Parkinson’s patients. We used tract-based spatial statistics to compare DTI data from 15 patients to 15 healthy, age- and education-matched controls. We then extracted mean values of fractional anisotropy (FA) and mean diffusivity (MD) within an a priori frontal mask. Executive function composite Z scores were regressed against these DTI indices, age, and total intracranial volume. In Parkinson’s patients, FA was related to executive composite scores, and both indices were related to Stroop interference scores. We conclude that white matter microstructural abnormalities contribute to cognitive deficits in Parkinson’s disease. Further work is needed to determine whether these white matter changes reflect the pathological process or a clinically important comorbidity.