Bilateral White Matter Research Articles

Novel Gene Mutation Variant in Hypomyelinating Leukodystrophy-8: A Case Report

The incidence of hypomyelinating leukodystrophies is approximately 1 in every 250,000–500,000 individuals in the population. Hypomyelinating leukodystrophy-8 (HLD-8) is characterized by classical clinical features, including modest intellectual deficits and early-onset progressive cerebellar ataxia, with or without oligodontia and/or hypogonadotropic hypogonadism. In this case report, we present a 34-year-old male who experienced gradually progressive behavioral and memory disturbances over the past 10 years, accompanied by imbalance while walking and complex partial seizures. The patient also exhibited oligodontia and moderate intellectual disability (IQ score: 45). Spasticity was observed in the lower limbs, with exaggerated deep tendon reflexes in all four limbs, and bilaterally extensor plantar responses were noted. Sensory examination results were within normal limits. Bilateral cerebellar signs were present, including gaze-evoked nystagmus in all directions, which was non-fatigable. MRI brain revealed generalized cerebral and cerebellar atrophy, as well as diffuse hyperintensities in T2-weighted images (T2W) and fluid-attenuated inversion recovery (FLAIR) in the bilateral cerebral white matter, with no basal ganglia involvement. The sagittal T1-weighted image (T1W) showed diffuse thinning of the corpus callosum. Whole-exome sequencing revealed a novel variant mutation of the POLR3B gene in HLD-8, specifically in Exon 20 [c.2125A>G (p.Met709Val)] and Exon 23 [c.2699G>A (p.Arg900His)]. Very few case reports and variant mutations on the POLR3B gene on chromosome 12q23.3 have been reported thus far.

A Case of the Anti-aquaporine-4 Antibody-negative Neuromyelitis Optica Spectrum Disorders Associated with Atopic Disease with High Concentration of Anti-IgE Autoantibody and HyperIgEemia

We report a 70-year-old male patient with the sero-negative neuromyelitis optica spectrum disorders (NMOSD) associated with atopic disease (AD). He was diagnosed with allergic rhinitis at the age of 20. When he was 61 years old, he subacutely developed orthostatic hypotension, bilateral optic neuritis, quadriparesis, urinary retention, and constipation. The laboratory results revealed allergen-specific IgE positivity for cryptomeria japonica and hinoki, hyperIgEemia, and Th (helper T cell) 1 dominance. The serological tests for autoantibodies revealed negative anti-aquaporine 4 antibody, and high concentration of anti-IgE autoantibody (anti-IgE AAb). Cerebrospinal fluid was negative for anti-myelin-oligodendrocyte glycoprotein antibody and glial fibrillary acidic protein antibody. Fluid-attenuated inversion recovery on brain magnetic resonance imaging (MRI) showed high signal intensities in bilateral cerebral deep white matter. T2 weighted image on spine MRI showed longitudinally extensive high signal intensities in the spinal cord, specifically involving C1 vertebral level to conus medullaris. Intravenous methylprednisolone (IVMP) and plasma exchange resulted in partial improvement. Following the onset of NMOSD, he had relapse of NMOSD four times. In each episode, IVMP was to be partially effective with anti-IgE AAb reduction. Anti-IgE AAb may be a reasonable clinical indicator of increased disease activity in the sero-negative NMOSD associated with AD.

Clinical prognostication in acute necrotizing encephalopathy of childhood: the role of magnetic resonance imaging severity assessment.

Acute necrotizing encephalopathy of childhood is a unique entity with bilateral gray and white matter involvement. The aim of this study is to explore whether the severity of findings on imaging scans is indicative of the prognosis and clinical outcomes for pediatric patients with acute necrotizing encephalopathy. A retrospective cross-sectional study was conducted on 42 patients diagnosed with acute necrotizing encephalopathy. A severity score based on MR imaging was computed for each patient, utilizing a point system determined by the existence of factors such as hemorrhage, cavitation, enhancement, diffusion restriction, and lesion location. The scoring was categorized into mild, moderate, and severe. Clinical outcomes were determined at the time of discharge and at follow-ups as mild disability, moderate disability, severe disability, and death according to the modified Rankin Scale. Associations were determined by Fisher's exact test, chi-square test, and one-way ANOVA. The study included 21 boys and 21 girls with a mean age of 71.5months. A statistically significant connection (P=0.027) was found between the severity score from MR imaging and the clinical outcome. A statistically significant relationship was also observed between diffusion restriction (P=0.008), cerebellar involvement (P=0.048), and an unfavorable clinical outcome. Additionally, individuals who experienced shock exhibited a correlation with adverse outcomes (P=0.01). In predicting the outcome of acute necrotizing encephalopathy, cerebellar involvement and presence of diffusion restriction were associated with worse clinical outcomes in our study. Developing a comprehensive MR-based severity score is crucial for improving diagnostic accuracy and patient outcomes. Our findings underscore the importance of including diffusion restriction and cerebellar involvement in the scoring system.

Understanding the mechanisms of fatigue in multiple sclerosis: linking interoception, metacognition and white matter dysconnectivity.

One of the most prominent symptoms in multiple sclerosis is pathological fatigue, often described by sufferers as one of the most debilitating symptoms, affecting quality of life and employment. However, the mechanisms of both, physical and cognitive fatigue in multiple sclerosis remain elusive. Here, we use behavioural tasks and quantitative MRI to investigate the neural correlates of interoception (the ability to sense internal bodily signals) and metacognition (the ability of the brain to assess its own performance), in modulating cognitive fatigue. Assuming that structural damage caused by multiple sclerosis pathology might impair the neural pathways subtending interoception and/or metacognition, we considered three alternative hypotheses to explain fatigue as a consequence of, respectively: (i) reduced interoceptive accuracy, (ii) reduced interoceptive insight or (iii) reduced global metacognition. We then explored associations between these behavioural measures and white matter microstructure, assessed by diffusion and magnetisation transfer MRI. Seventy-one relapsing-remitting multiple sclerosis patients participated in this cross-sectional study (mean age 43, 62% female). Patient outcomes relevant for fatigue were measured, including disability, disease duration, depression, anxiety, sleepiness, cognitive function, disease modifying treatment and quality of life. Interoceptive and metacognitive parameters were measured using heartbeat tracking and discrimination tasks, and metacognitive visual and memory tasks. MRI was performed in 69 participants, including diffusion tensor MRI, neurite orientation dispersion and density imaging and quantitative magnetisation transfer. Associations between interoception and metacognition and the odds of high cognitive fatigue were tested by unconditional binomial logistic regression. The odds of cognitive fatigue were higher in the people with low interoceptive insight (P = 0.03), while no significant relationships were found between fatigue and other interoceptive or metacognitive parameters, suggesting a specific impairment in interoceptive metacognition, rather than interoception generally, or metacognition generally. Diffusion MRI-derived fractional anisotropy and neurite density index showed significant (P < 0.05) negative associations with cognitive fatigue in a widespread bilateral white matter network. Moreover, there was a significant (P < 0.05) interaction between cognitive fatigue and interoceptive insight, suggesting that the poorer the white matter structure, the lower the interoceptive insight, and the worse the fatigue. The results point towards metacognitive impairment confined to the interoceptive domain, in relapsing-remitting patients with cognitive fatigue. The neural basis of this impairment is supported by a widespread white matter network in which loss of neurite density plays a role.

Early Biomarkers in the Prediction of Later Functional Impairment in Preterm Children With Cerebral Palsy

BackgroundTo identify early biomarkers that could predict later functional capabilities in preterm children with later cerebral palsy (CP). MethodsData from 968 preterm children with later CP were extracted from the Canadian Cerebral Palsy Registry. One hundred eighty-two infants were born before 27 weeks of gestation, 461 infants were born between 27 and 33 weeks, and 325 infants were born between 34 and 37 weeks. Univariate and chi-square analyses were conducted to measure the association between early objective biomarkers and later mobility status defined as Gross Motor Function Classification System (GMFCS) levels IV and V as well as tube feeding dependence. ResultsUnivariate analysis suggested no significant association between GMFCS levels IV and V or impaired feeding status and bilateral white matter injury on magnetic resonance imaging, high-grade intraventricular hemorrhage on head ultrasound, chorioamnionitis, a birth weight of 1000 to 1500 g or <1000 g, as well as an Apgar score of ≤5 at five minutes of life. Similar results were found for gestational age <28 weeks at birth. Only a significant association between GMFCS levels IV and V and a cord or first hour of life pH of ≤7 was reported (mobility status: odds ratio [OR] 1.95, 95% confidence interval [CI] 1.09 to 3.57) and feeding status: OR 2.23, CI 0.97 to 4.65)]. ConclusionsPrediction of functional outcomes based on specific early biomarkers appears hard to obtain in children with CP born preterm in contrast to those born at term. The complications and causal pathways inherent to prematurity may contribute to making prognostication less determinant.

L2-hydroxyglutaric aciduria presenting with learning disability and cerebellar signs: A case report

L-2-hydroxyglutaric aciduria (L2HGA) is a rare, autosomal recessive neurometabolic disorder due to variants in the L2HGDH gene, which encodes L-2-hydroxyglutarate dehydrogenase (L2HGDH), an enzyme involved in tricarboxylic acid cycle. Deficiency of L2HGDH causes leukoencephalopathy predominantly affecting the cerebellum. This case presents L2HGA in a 12-year-old Sri Lankan boy born to third-degree consanguineous parents, who also showed learning disability and bilateral cerebellar signs. Magnetic resonance imaging (MRI) of the brain revealed T2/FLAIR hyperintensities in bilateral symmetrical subcortical white matter involving the cerebellum. A diagnosis of 2-hydroxyglutaric aciduria was made after a massive peak of 2-hydroxyglutaric acid (2HG) was observed in the analysis of urine organic acids (UOA) using gas chromatography/mass spectrometry. Genetic variant analysis revealed two heterozygous pathogenic variants in the L2HGDH gene, confirming the genetic diagnosis of autosomal recessive L2HGA. Parental genetic testing confirmed the trans phase of the variants in the index patient and their carrier status of a pathogenic L2HGDH variant. Despite typical clinical features and classical MRI findings, initial clues toward the diagnosis are mainly derived from the UOA analysis. In conclusion, this case underscores the paramount importance of analyzing the UOA profile in the process of identifying rare metabolic causes, such as L2HGA, that contribute to learning disability with neurological involvement in children.

A case of MERS presenting with acute motor aphasia and tetraparesis and literature review

BackgroundMild encephalopathy wıth reversible splenial lesions (MERS) are a clinical–radiological diagnosis that can be diagnosed with radiological imaging and can be accompanied by impaired consciousness, aphasia, headache, and paralysis. MERS can be divided into two different types based on radiological findings; Involvement of the splenium is seen in type 1, and involvement of the splenium and deep white matter is seen in type 2. MERS Type 2 is very rare in adults. Here, we describe a patient diagnosed with MERS Type 2 and our therapeutic intervention.Case presentationA 22-year-old woman presented with slurred speech, weakness in the extremities and headache that started 14 h ago. The patient had sore throat and fever of 37.6 °C for 2 days, and medical history or family history were unremarkable. Neurological examination revealed that she was conscious, cooperative, with no signs of meningeal irritation. Speech comprehension, naming, and repetition were preserved, motor examination revealed 5/5 left upper extremity strength, 4/5 right upper extremity strength, and 2/5 bilateral lower extremity strength. Diffusion-weighted magnetic resonance imaging (MRI-DWI) revealed bilateral deep white matter and splenium symmetrical diffusion restriction. Blood tests showed high C-reactive protein (CRP) and no leukocytosis. No cells were detected in the cerebrospinal fluid (CSF), protein was 151 mg/dl, glucose was within normal limits. The patient, who developed quadriparesis during follow-up, was started on pulse dose steroids. Neurological examination improved to patient’s baseline at the 12th hour of treatment. In the 72nd hour control MRI-DWI, it was seen that the lesions had regressed. Culture/Polymerase chain reaction (PCR) for bacterial/viral infection agents came back negative. After steroids were given for 5 days, patient was discharged at her baseline.ConclusionsMERS is a rare diagnosis in adults and can be radiologically confused with acute toxic leukoencephalopathy. It can be distinguished clinically by the absence of prior infection, fever, and toxic agent exposure. Although there is no consensus in the literature regarding the treatment, the clinical picture improved rapidly after steroid in our case. Despite being rare, it should be considered in the differential diagnosis of patients with deep white matter lesions in adults.

Brain MRI findings in paediatric genetic disorders associated with white matter abnormalities.

To describe the specific brain magnetic resonance imaging (MRI) patterns of the paediatric genetic disorders associated with white matter abnormalities in Northern Finland. In this retrospective population-based longitudinal study, brain MRI scans accumulated from 1990 to 2019 at Oulu University Hospital, Finland, were assessed. Inclusion criteria were defined as leukodystrophies or genetic diseases with significant white matter abnormalities that did not meet the criteria for leukodystrophy, at least one brain MRI, and age under 18 years at diagnosis. A total of 83 patients (48 males, 35 females) were found with 52 different diseases. The median age at the time of the brain MRI was 22 months (interquartile range [IQR] = 46 months). In 72 (87%) of the children, brain MRIs revealed abnormal findings, including cerebral white matter abnormalities (n = 49, 59%), brainstem signal abnormalities (n = 28, 34%), thinning of the corpus callosum (n = 30, 36%), delayed myelination (n = 11, 13%), and permanent hypomyelination (n = 9, 11%). Symmetrical and bilateral white matter signal patterns of the brain MRI should raise suspicion of genetic disorders when the clinical symptoms are compatible. This study illustrates brain imaging patterns of childhood-onset genetic disorders in a population in Northern Finland and improves the diagnostic accuracy of rare genetic disorders.

Structural and functional features characterizing the brains of individuals with higher controllability of motor imagery

Motor imagery is a higher-order cognitive brain function that mentally simulates movements without performing the actual physical one. Although motor imagery has attracted the interest of many researchers, and mental practice utilizing motor imagery has been widely used in sports training and post-stroke rehabilitation, neural bases that determine individual differences in motor imagery ability are not well understood. In this study, using controllability of motor imagery (CMI) test that can objectively evaluate individual ability to manipulate one’s imaginary postures, we examined structural and functional features characterizing the brains of individuals with higher controllability of motor imagery, by analyzing T1-weighted structural MRI data obtained from 89 participants and functional MRI data obtained from 28 of 89 participants. The higher CMI test scorers had larger volume in the bilateral superior frontoparietal white matter regions. The CMI test activated the bilateral dorsal premotor cortex (PMD) and superior parietal lobule (SPL); specifically, the left PMD and/or the right SPL enhanced functional coupling with the visual body, somatosensory, and motor/kinesthetic areas in the higher scorers. Hence, controllability of motor imagery is higher for those who well-develop superior frontoparietal network, and for those whose this network accesses these sensory areas to predict the expected multisensory experiences during motor imagery. This study elucidated for the first time the structural and functional features characterizing the brains of individuals with higher controllability of motor imagery, and advanced understanding of individual differences in motor imagery ability.

Tralopyril poisoning due to respiratory exposure

Introduction Tralopyril is a metabolite of the pesticide chlorfenapyr. Direct toxicity by tralopyril has not been described. We report two cases of tralopyril poisoning via inhalation. Case presentations Two workers developed heat intolerance, diaphoresis, and weight loss after occupational inhalational exposure to tralopyril. Patient 1: The exposure was due to the absence of respiratory protection. Magnetic resonance imaging showed abnormal signals in the bilateral periventricular white matter, corpus callosum, basal ganglia, brainstem, and spinal cord. The patient’s blood tralopyril concentrations on days 1, 3, 5, 8, and 11 post-admission were 1.09 mg/L, 1.04 mg/L, 1.01 mg/L, 0.71 mg/L, and 0.313 mg/L, respectively. Haemoperfusion (HA330), haemoperfusion (HA380), and haemodiafiltration were performed on days 1–3, 5–8, and 9–10, respectively. Patient 2: The patient’s symptoms followed inappropriate use of respiratory protection. His blood tralopyril concentrations on days 1, 4, 5, and 6 were 0.592 mg/L, 0.482 mg/L, 0.370 mg/L, and 0.228 mg/L, respectively. Discussion The patients presented with features typical of chlorfenapyr poisoning, which suggests that tralopyril is the main toxic metabolite of chlorfenapyr. Conclusion Tralopyril can be absorbed by inhalation, leading to delayed clinical symptoms and organ damage, including toxic encephalopathy and spinal cord damage.

Premenopausal bilateral oophorectomy and brain white matter brain integrity in later-life.

Premenopausal bilateral oophorectomy (PBO) is associated with later-life cognition, but the underlying brain changes remain unclear. We assessed the impact of PBO and PBO age on white matter integrity. Female participants with regional diffusion tensor imaging (DTI) metrics of fractional anisotropy (FA) and mean diffusivity (MD) were included (22 with PBO<40 years; 43 with PBO 40-45 years; 39 with PBO 46-49 years; 907 referents without PBO<50 years). Linear regression models adjusted for age and apolipoprotein E (APOE) genotype. Females with PBO<40 years, compared to referents, had lower FA and higher MD in the anterior corona radiata, genu of the corpus collosum, inferior fronto-occipital fasciculus, superior occipital, and superior temporal white matter. Females who underwent PBO between 45 and 49 also had some changes in white matter integrity. Females who underwent PBO<40 years had reduced white matter integrity across multiple regions in later-life. These results are important for females considering PBO for noncancerous conditions. Females with premenopausal bilateral oophorectomy (PBO)<40 years had lower FA versus referents. Females with PBO<40 years had higher MD in many regions versus referents. Adjusting for estrogen replacement therapy use did not attenuate results. Females with PBO 45-49 years also had some white matter changes versus referents.

Understanding the role of cerebellum in early Parkinson’s disease: a structural and functional MRI study

Increasing evidence suggests that the cerebellum may have a role in the pathophysiology of Parkinson’s disease (PD). Hence, the scope of this study was to investigate whether there are structural and functional alterations of the cerebellum and whether they correlate with motor and non-motor symptoms in early PD patients. Seventy-six patients with early PD and thirty-one age and sex-matched healthy subjects (HS) were enrolled and underwent a 3 T magnetic resonance imaging (MRI) protocol. The following MRI analyses were performed: (1) volumes of 5 cerebellar regions of interest (sensorimotor and cognitive cerebellum, dentate, interposed, and fastigial nuclei); (2) microstructural integrity of the cerebellar white matter connections (inferior, middle, and superior cerebellar peduncles); (3) functional connectivity at rest of the 5 regions of interest already described in point 1 with the rest of brain. Compared to controls, early PD patients showed a significant decrease in gray matter volume of the dentate, interposed and fastigial nuclei, bilaterally. They also showed abnormal, bilateral white matter microstructural integrity in all 3 cerebellar peduncles. Functional connectivity of the 5 cerebellar regions of interest with several areas in the midbrain, basal ganglia and cerebral cortex was altered. Finally, there was a positive correlation between abnormal functional connectivity of the fastigial nucleus with the volume of the nucleus itself and a negative correlation with axial symptoms severity. Our results showed that structural and functional alterations of the cerebellum are present in PD patients and these changes contribute to the pathophysiology of PD in the early phase.

Relationship between sleep, physical fitness, brain microstructure, and cognition in healthy older adults: A pilot study

BackgroundThere is a critical need for neuroimaging markers of brain integrity to monitor effects of modifiable lifestyle factors on brain health. This observational, cross-sectional study assessed relationships between brain microstructure and sleep, physical fitness, and cognition in healthy older adults. MethodsTwenty-three adults aged 60 and older underwent whole-brain multi-shell diffusion imaging, comprehensive cognitive testing, polysomnography, and exercise testing. Neurite Orientation Dispersion and Density Imaging (NODDI) was used to quantify neurite density (NDI) and orientation dispersion (ODI). Diffusion tensor imaging (DTI) was used to quantify axial diffusivity (AxD), fractional anisotropy (FA), mean diffusivity (MD), and radial diffusivity (RD). Relationships between sleep efficiency (SE), time and percent in N3 sleep, cognitive function, physical fitness (VO2 peak) and the diffusion metrics in regions of interest and the whole brain were evaluated. ResultsHigher NDI in bilateral white and gray matter was associated with better executive functioning. NDI in the right anterior cingulate and adjacent white matter was positively associated with language skills. Higher NDI in the left posterior corona radiata was associated with faster processing speed. Physical fitness was positively associated with NDI in the left precentral gyrus and corticospinal tract. N3 % was positively associated with NDI in the left caudate and right pre- and postcentral gyri. Higher ODI in the left putamen and adjacent white matter was associated with better executive function. ConclusionNDI and ODI derived from NODDI are potential neuroimaging markers for associations between brain microstructure and modifiable risk factors in aging. If these associations are observable in clinical samples, NODDI could be incorporated into clinical trials assessing the effects of modifiable risk factors on brain integrity in aging and neurodegenerative diseases.

Transient brain structure changes after high phenylalanine exposure in adults with phenylketonuria.

Phenylketonuria is a rare metabolic disease resulting from a deficiency of the enzyme phenylalanine hydroxylase. Recent cross-sectional evidence suggests that early-treated adults with phenylketonuria exhibit alterations in cortical grey matter compared to healthy peers. However, the effects of high phenylalanine exposure on brain structure in adulthood need to be further elucidated. In this double-blind, randomised, placebo-controlled crossover trial, we investigated the impact of a four-week high phenylalanine exposure on the brain structure and its relationship to cognitive performance and metabolic parameters in early-treated adults with phenylketonuria. Twenty-eight adult patients with early-treated classical phenylketonuria (19-48 years) underwent magnetic resonance imaging before and after the four-week phenylalanine and placebo interventions (four timepoints). Structural T1-weighted images were preprocessed and evaluated using DL+DiReCT, a deep-learning-based tool for brain morphometric analysis. Cortical thickness, white matter volume, and ventricular volume were compared between the phenylalanine and placebo periods. Brain phenylalanine levels were measured using 1H spectroscopy. Blood levels of phenylalanine, tyrosine, and tryptophan were assessed at each of the four timepoints, along with performance in executive functions and attention. Blood phenylalanine levels were significantly higher after the phenylalanine period (1441µmol/L) than after the placebo period (873µmol/L, P<0.001). Morphometric analyses revealed a statistically significant decrease in cortical thickness in 17 out of 60 brain regions after the phenylalanine period compared to placebo. The largest decreases were observed in the right pars orbitalis (point estimate=-0.095mm, P<0.001) and the left lingual gyrus (point estimate=-0.070mm, P<0.001). Bilateral white matter and ventricular volumes were significantly increased after the phenylalanine period. However, the structural alterations in the Phe-placebo group returned to baseline measures following the washout and placebo period. Additionally, elevated blood and brain phenylalanine levels were related to increased bilateral white matter volume (rs=0.43 to 0.51, P≤0.036) and decreased cortical thickness (rs=-0.62 to -0.39, not surviving FDR correction) after the phenylalanine and placebo periods. Moreover, decreased cortical thickness was correlated with worse cognitive performance after both periods (rs=-0.54 to -0.40, not surviving FDR correction). These findings provide evidence that a four-week high phenylalanine exposure in adults with phenylketonuria results in transient reductions of the cortical grey matter and increases in white matter volume. Further research is needed to determine the potential long-term impact of high phenylalanine levels on brain structure and function in adults with phenylketonuria.

Diffusion imaging markers of accelerated aging of the lower cingulum in subjective cognitive decline.

Alzheimer's Disease (AD) typically starts in the medial temporal lobe, then develops into a neurodegenerative cascade which spreads to other brain regions. People with subjective cognitive decline (SCD) are more likely to develop dementia, especially in the presence of amyloid pathology. Thus, we were interested in the white matter microstructure of the medial temporal lobe in SCD, specifically the lower cingulum bundle that leads into the hippocampus. Diffusion tensor imaging (DTI) has been shown to differentiate SCD participants who will progress to mild cognitive impairment from those who will not. However, the biology underlying these DTI metrics is unclear, and results in the medial temporal lobe have been inconsistent. To better characterize the microstructure of this region, we applied DTI to cognitively normal participants in the Cam-CAN database over the age of 55 with cognitive testing and diffusion MRI available (N = 325, 127 SCD). Diffusion MRI was processed to generate regional and voxel-wise diffusion tensor values in bilateral lower cingulum white matter, while T1-weighted MRI was processed to generate regional volume and cortical thickness in the medial temporal lobe white matter, entorhinal cortex, temporal pole, and hippocampus. SCD participants had thinner cortex in bilateral entorhinal cortex and right temporal pole. No between-group differences were noted for any of the microstructural metrics of the lower cingulum. However, correlations with delayed story recall were significant for all diffusion microstructure metrics in the right lower cingulum in SCD, but not in controls, with a significant interaction effect. Additionally, the SCD group showed an accelerated aging effect in bilateral lower cingulum with MD, AxD, and RD. The diffusion profiles observed in both interaction effects are suggestive of a mixed neuroinflammatory and neurodegenerative pathology. Left entorhinal cortical thinning correlated with decreased FA and increased RD, suggestive of demyelination. However, right entorhinal cortical thinning also correlated with increased AxD, suggestive of a mixed pathology. This may reflect combined pathologies implicated in early AD. DTI was more sensitive than cortical thickness to the associations between SCD, memory, and age. The combined effects of mixed pathology may increase the sensitivity of DTI metrics to variations with age and cognition.

Clinical and Diagnostic Features of West Nile Virus Neuroinvasive Disease in New York City.

West Nile virus (WNV) neuroinvasive disease (WNND) occurs in approximately 1 percent of WNV-infected patients and typically presents as encephalitis, meningitis, or acute flaccid paralysis (AFP). WNND remains a difficult inpatient diagnosis, creating significant challenges for prognostication and therapy selection. We characterized the clinical and diagnostic features of WNND cases at two major academic medical centers in New York City in routine clinical practice. We retrospectively reviewed the charts of thirty-six patients with WNND, including twenty-six encephalitis, four meningitis, and six AFP cases. The most common presenting symptoms were fever (86.1%) and gastrointestinal symptoms (38.9%) in addition to altered mental status (72.2%), lethargy (63.9%), gait disturbances (46.2%), and headache (44.4%). Fourteen (48.3%) patients displayed acute magnetic resonance imaging (MRI) findings, particularly T2 hyperintensities in the bilateral thalami, brainstem, and deep white matter. New York State Department of Health WNV CSF IgM testing was utilized for diagnosis in 58.3% of patients; however, just 38.1% had the result by discharge, compared to 85.6% of those who underwent serum IgM testing. The median length of stay was 13.5 days, 38.9% were intubated, and three patients (8.9%) died during acute hospitalization. Our findings underscore the morbidity, mortality, and diagnostic challenges of WNND, suggesting the potential utility of serum IgM testing in combination with confirmatory CSF testing to expedite diagnosis in the acute setting.

Clinical phenotype and genetic function analysis of a family with hypomyelinating leukodystrophy-7 caused by POLR3A mutation

Hypomyelinating leukodystrophy (HLD) is a rare genetic heterogeneous disease that can affect myelin development in the central nervous system. This study aims to analyze the clinical phenotype and genetic function of a family with HLD-7 caused by POLR3A mutation. The proband (IV6) in this family mainly showed progressive cognitive decline, dentin dysplasia, and hypogonadotropic hypogonadism. Her three old brothers (IV1, IV2, and IV4) also had different degrees of ataxia, dystonia, or dysarthria besides the aforementioned manifestations. Their brain magnetic resonance imaging showed bilateral periventricular white matter atrophy, brain atrophy, and corpus callosum atrophy and thinning. The proband and her two living brothers (IV2 and IV4) were detected to carry a homozygous mutation of the POLR3A (NM_007055.4) gene c. 2300G > T (p.Cys767Phe), and her consanguineous married parents (III1 and III2) were p.Cys767Phe heterozygous carriers. In the constructed POLR3A wild-type and p.Cys767Phe mutant cells, it was seen that overexpression of wild-type POLR3A protein significantly enhanced Pol III transcription of 5S rRNA and tRNA Leu-CAA. However, although the mutant POLR3A protein overexpression was increased compared to the wild-type protein overexpression, it did not show the expected further enhancement of Pol III function. On the contrary, Pol III transcription function was frustrated (POLR3A, BC200, and tRNA Leu-CAA expression decreased), and MBP and 18S rRNA expressions were decreased. This study indicates that the POLR3A p.Cys767Phe variant caused increased expression of mutated POLR3A protein and abnormal expression of Pol III transcripts, and the mutant POLR3A protein function was abnormal.

Associations between cerebellar development and autistic traits during adolescence: a population-based cohort study

IntroductionBrain maturation is associated with adolescent socio-cognitive development. The lateral posterior region of the cerebellum plays a critical role in higher cognitive processes, and deviations of this region are associated with autism-related behaviors. Hence, it is plausible that developmental changes in this region of the cerebellum during adolescence are different along a variation in autistic traits. Additionally, its difference may be moderated by parental age at birth and weight growth during infancy, which have effects on brain development.ObjectivesThe aim of this study was two folds: (1) to test whether cerebellar development during adolescence is different along a variation in autistic traits (2) to test whether parental age at birth and weight growth during infancy moderate the results of (1).MethodsLongitudinal study was conducted over a 6-year period with 256, 230 and 187 participants ranging from 10.5 to 17.6 years, observing adolescent development respectively at 2-year time periods. We undertook a detailed investigation into differences in the lateral posterior region of the cerebellum volume. The 50-item Autism-Spectrum Quotient (AQ) was rated by primary parents. Weight growth and parental age were evaluated using maternal and child health handbook records. A multiple regression analysis was performed to examine whether AQ subscales, sex, and their interactions affected cerebellar development. Moderation analysis assessed whether parental age and weight growth moderated associations between cerebellar development and autistic traits. All participants provided written informed consent, and the study was approved by the Ethics Committee (No.10069).ResultsInteractions between sex and attention switching and sex and attention to detail were significantly associated with cerebellar development in the bilateral gray matter (GM) and white matter (WM) of Crus I and Crus II (Fig1, 2). Simple slope analyses showed that the slopes of cerebellar development were significant for girls (pFDR &lt; 0.001). Although no significant interaction was found between them, the main effect of attention to detail was significantly associated with cerebellar development in WM of VIIB (pFDR = 0.006). Further, moderation analysis found that the association between the cerebellar development and autistic traits were significantly moderated by maternal age; the magnitude of its effect was significant for high maternal age in boys (pFDR = 0.036, Fig3). Paternal age, early (0-9 months) and late weight growth (4-18 months) also moderated associations between them, however, no significance remained after FDR controlling.Image:Image 2:Image 3:ConclusionsThere are significant associations between cerebellar development during adolescence and autistic traits, and its pattern of association can be moderated by parental ages at birth and weight growth during infancy in a cerebellar region- and sex-specific manner.Disclosure of InterestNone Declared

Experimental Ischemic Stroke Induces Secondary Bihemispheric White Matter Degeneration and Long-Term Cognitive Impairment.

Clinical studies have identified widespread white matter degeneration in ischemic stroke patients. However, contemporary research in stroke has predominately focused on the infarct and periinfarct penumbra regions. The involvement of white matter degeneration after ischemic stroke and its contribution to post-stroke cognitive impairment and dementia (PSCID) has remained less explored in experimental models. In this study, we examined the progression of locomotor and cognitive function up to 4 months after inducing ischemic stroke by middle cerebral artery occlusion in young adult rats. Despite evident ongoing locomotor recovery, long-term cognitive and affective impairments persisted after ischemic stroke, as indicated by Morris water maze, elevated plus maze, and open field performance. At 4 months after stroke, multimodal MRI was conducted to assess white matter degeneration. T2-weighted MRI (T2WI) unveiled bilateral cerebroventricular enlargement after ischemic stroke. Fluid Attenuated Inversion Recovery MRI (FLAIR) revealed white matter hyperintensities in the corpus callosum and fornix across bilateral hemispheres. A positive association between the volume of white matter hyperintensities and total cerebroventricular volume was noted in stroke rats. Further evidence of bilateral white matter degeneration was indicated by the reduction of fractional anisotropy and quantitative anisotropy at bilateral corpus callosum in diffusion-weighted MRI (DWI) analysis. Additionally, microglia and astrocyte activation were identified in the bilateral corpus callosum after stroke. Our study suggests that experimental ischemic stroke induced by MCAO in young rat replicate long-term cognitive impairment and bihemispheric white matter degeneration observed in ischemic stroke patients. This model provides an invaluable tool for unraveling the mechanisms underlying post-stroke secondary white matter degeneration and its contribution to PSCID.

The Phenotypic and Genotypic Spectrum of CSF1R-Related Disorder in China.

Colony-stimulating factor 1 receptor (CSF1R)-related disorder (CRD) is a rare autosomal dominant disease. The clinical and genetic characteristics of Chinese patients have not been elucidated. The objective of the study is to clarify the core features and influence factors of CRD patients in China. Clinical and genetic-related data of CRD patients in China were collected. Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Sundal MRI Severity Score were evaluated. Whole exome sequencing was used to analyze the CSF1R mutation status. Patients were compared between different sexes, mutation types, or mutation locations. A total of 103 patients were included, with a male-to-female ratio of 1:1.51. The average age of onset was (40.75 ± 8.58). Cognitive impairment (85.1%, 86/101) and parkinsonism (76.2%, 77/101) were the main clinical symptoms. The most common imaging feature was bilateral asymmetric white matter changes (100.0%). A total of 66 CSF1R gene mutants (22 novel mutations) were found, and 15 of 92 probands carried c.2381 T > C/p.I794T (16.30%). The MMSE and MoCA scores (17.0 [9.0], 11.90 ± 7.16) of female patients were significantly lower than those of male patients (23.0 [10.0], 16.36 ± 7.89), and the white matter severity score (20.19 ± 8.47) of female patients was significantly higher than that of male patients (16.00 ± 7.62). There is no statistical difference in age of onset between male and female patients. The core manifestations of Chinese CRD patients are progressive cognitive decline, parkinsonism, and bilateral asymmetric white matter changes. Compared to men, women have more severe cognitive impairment and imaging changes. c.2381 T > C/p.I794T is a hotspot mutation in Chinese patients. © 2024 International Parkinson and Movement Disorder Society.