A Bidirectional Mendelian Randomization Study of Gut Microbiota and Cerebral Small Vessel Disease.

BACKGROUND: The causal nature of gut microbiota and cerebral small vessel disease (CSVD) is still obscure regardless of evidence supporting their observational correlations. OBJECTIVES: The primary objective of this research is to investigate the potentially pathogenic or protective causal impacts of specific gut microbiota on various neuroimaging subtypes of CSVD. METHODS: We obtained the latest summary-level genome-wide databases for gut microbiota and 9 CSVD traits. The univariable and multivariable Mendelian randomization (MR) studies were conducted to examine the possible causal link between exposure and outcome. Meanwhile, we conducted sensitivity analyses sequentially, containing the heterogeneity, pleiotropy, and leave-one-out analysis. Additionally, to clarify the potential bidirectional causality, the causality from CSVD traits to the identified gut microbiota was implemented through reverse MR analysis. RESULTS: The univariable MR analysis identified 22 genetically predicted bacterial abundances that were correlated with CSVD traits. Although conditioning on macronutrient dietary compositions, 2 suggestive relationships were retained using the multivariable MR analysis. Specifically, the class Negativicutes and order Selenomonadales exhibited a negative causal association with strictly lobar cerebral microbleeds, one neuroimaging trait of CSVD. There is insufficient evidence indicating the presence of heterogeneity and horizontal pleiotropy. Furthermore, the identified causal relationship was not driven by any single nucleotide polymorphism. The results of the reverse MR analysis did not reveal any statistically significant causality from CSVD traits to the identified gut microbiota. CONCLUSIONS: Our study indicated several suggestive causal effects from gut microbiota to different neuroimaging subtypes of CSVD. These findings provided a latent understanding of the pathogenesis of CSVD from the perspective of the gut-brain axis.

Process approach as a cognitive biomarker related to gray matter volume in mild cognitive impairment and Alzheimer's disease.

BACKGROUND: Process approach is valuable for memory assessment in Alzheimer's disease (AD) and mild cognitive impairment (MCI), yet its underlying mechanisms remain elusive. This study aims to synergize the process approach with brain structure analysis to explore both the discriminative capacity and potential mechanisms underlying the process approach. METHODS: 37 subjects of MCI, 35 subjects of AD and 38 subjects of healthy control (HC) were included. The process approach in Auditory Verbal Learning Test (AVLT), including discriminability (A'), response bias (B"D), semantic clustering (LBCsem) and serial clustering (LBCser) was performed. The gray matter volume (GMV) was analyzed by voxel-based morphometry. Receiver operating characteristic (ROC) analysis and partial correlations were conducted to explore the value of the process approach and investigate the relationship between the process approach, traditional indices of AVLT and GMV. RESULTS: ROC analysis showed the value of A', B"D and LBCser in differentiating MCI and AD. Combining AVLT-Immediately Recall (AVLT-IR) and LBCser showed a higher value in diagnosing MCI. Partial correlations revealed that in the MCI group, A' and B"D were mainly positively associated with GMV of the hippocampus and temporal lobe. CONCLUSION: This study indicated that the process approach is a promising cognitive biomarker to detect MCI and AD.

[Process Approach in Memory Assessment of Patients With Alzheimer's Disease and Mild Cognitive Impairment:A Review].

The process approach,a set of analytical methods used in neuropsychology,quantifies the word-list learning tests and conventional analytical methods and fully reflects the memory profile of the subject.Therefore,it is widely used in the memory assessment of patients with Alzheimer's disease(AD)and mild cognitive impairment(MCI).The common indices of process approach,such as learning slope,semantic clustering,serial position effects,discriminability,and response bias,are key components of memory assessment.This article reviews the application of common indices of process approach in memory assessment of AD and MCI patients and discusses the shortcomings and future research directions of process approach.

Altered dynamic functional network connectivity and topological organization variance in patients with white matter hyperintensities.

White matter hyperintensities (WMHs) of presumed vascular origin are important imaging biomarkers of cerebral small vessel disease (CSVD). Previous studies have verified abnormal functional brain networks in CSVD. However, most of these studies rely on static functional connectivity, and only a few focus on the varying severity of the WMHs. Hence, our study primarily explored the disrupted dynamic functional network connectivity (dFNC) and topological organization variance in patients with WMHs. This study included 38 patients with moderate WMHs, 47 with severe WMHs, and 68 healthy controls (HCs). Ten independent components were chosen using independent component analysis based on resting-state functional magnetic resonance imaging. The dFNC of each participant was estimated using sliding windows and k-means clustering. We identified three reproducible dFNC states. Among them, patients with WMHs had a significantly higher occurrence in the sparsely connected State 1, but a lower occurrence and shorter duration in the positive and stronger connected State 3. Regarding topological organization variance, patients with WMHs showed higher variance in local efficiency but not global efficiency compared to HCs. Among the WMH subgroups, patients with severe WMHs showed similar but more obvious alterations than those with moderate WMHs. These altered network characteristics indicated an imbalance between the functional segregation and integration of brain networks, which was correlated with global cognition, memory, executive functions, and visuospatial abilities. Our study confirmed aberrant dFNC state metrics and topological organization variance in patients with moderate-to-severe WMHs; thus, it might provide a new pathway for exploring the pathogenesis of cognitive impairment.

[Changes in Plasma Amyloid-ß Level and Their Relationship With White Matter Microstructure in Patients With Mild Cognitive Impairment].

Objective To investigate the changes in plasma amyloid-ß (Aß) level and their relationship with white matter microstructure in the patients with amnesic mild cognitive impairment(aMCI) and vascular mild cognitive impairment (vMCI).Methods A total of 36 aMCI patients,20 vMCI patients,and 34 sex and age matched healthy controls (HC) in the outpatient and inpatient departments of the First Affiliated Hospital of Anhui Medical University were enrolled in this study.Neuropsychological scales,including the Mini-Mental State Examination,the Montreal Cognitive Assessment,and the Activity of Daily Living Scale,were employed to assess the participants.Plasma samples of all the participants were collected for the measurement of Aß42 and Aß40 levels.All the participants underwent magnetic resonance scanning to obtain diffusion tensor imaging (DTI) data.The DTI indexes of 48 white matter regions of each individual were measured (based on the ICBM-DTI-81 white-matter labels atlas developed by Johns Hopkins University),including fractional anisotropy (FA) and mean diffusivity (MD).The cognitive function,plasma Aß42,Aß40,and Aß42/40 levels,and DTI index were compared among the three groups.The correlations between the plasma Aß42/40 levels and DTI index of aMCI and vMCI patients were analyzed.Results The Mini-Mental State Examination and the Montreal Cognitive Assessment scores of aMCI and vMCI groups were lower than those of the HC group (all P<0.001).There was no significant difference in the Activity of Daily Living Scale score among the three groups (P=0.654).The plasma Aß42 level showed no significant difference among the three groups (P=0.227).The plasma Aß40 level in the vMCI group was higher than that in the HC group (P=0.014),while it showed no significant difference between aMCI and HC groups (P=1.000).The plasma Aß42/40 levels in aMCI and vMCI groups showed no significant differences from that in the HC group (P=1.000,P=0.105),while the plasma Aß42/40 level was lower in the vMCI group than in the aMCI group (P=0.016).The FA value of the left anterior limb of internal capsule in the vMCI group was lower than those in HC and aMCI groups (all P=0.001).The MD values of the left superior corona radiata,left external capsule,left cingulum (cingulate gyrus),and left superior fronto-occipital fasciculus in the vMCI group were higher than those in HC (P=0.024,P=0.001,P=0.003,P<0.001) and aMCI (P=0.015,P=0.004,P=0.019,P=0.001) groups,while the MD values of the right posterior limb of internal capsule (P=0.005,P=0.001) and left cingulum (hippocampus) (P=0.017,P=0.031) in the aMCI and vMCI groups were higher than those in the HC group.In the aMCI group,plasma Aß42/40 level was positively correlated with FA of left posterior limb of internal capsule (r=0.403,P=0.015) and negatively correlated with MD of the right fonix (r=-0.395,P=0.017).In the vMCI group,plasma Aß42/40 level was positively correlated with FA of the right superior cerebellar peduncle and the right anterior limb of internal capsule (r=0.575,P=0.008;r=0.639,P=0.002),while it was negatively correlated with MD of the right superior cerebellar peduncle and the right anterior limb of internal capsule (r=-0.558,P=0.011;r=-0.626,P=0.003).Conclusions Plasma Aß levels vary differently in the patients with aMCI and vMCI.The white matter regions of impaired microstructural integrity differ in the patients with different dementia types in the early stage.The plasma Aß levels in the patients with aMCI and vMCI are associated with the structural integrity of white matter,and there is regional specificity between them.

Uncovering of Key Pathways and miRNAs for Intracranial Aneurysm Based on Weighted Gene Co-Expression Network Analysis.

BACKGROUND: Intracranial aneurysm (IA) is a serious cerebrovascular disease. The identification of key regulatory genes can provide research directions for early diagnosis and treatment of IA. METHODS: Initially, the miRNA and mRNA data were downloaded from the Gene Expression Omnibus database. Subsequently, the limma package in R was used to screen for differentially expressed genes. In order to investigate the function of the differentially expressed genes, a functional enrichment analysis was performed. Moreover, weighted gene co-expression network analysis (WGCNA) was performed to identify the hub module and hub miRNAs. The correlations between miRNAs and mRNAs were assessed by constructing miRNA-mRNA regulatory networks. In addition, in vitro validation was performed. Finally, diagnostic analysis and electronic expression verification were performed on the GSE122897 dataset. RESULTS: In the present study, 955 differentially expressed mRNAs (DEmRNAs, 480 with increased and 475 with decreased expression) and 46 differentially expressed miRNAs (DEmiRNAs, 36 with increased and 10 with decreased expression) were identified. WGCNA demonstrated that the yellow module was the hub module. Moreover, 16 hub miRNAs were identified. A total of 1,124 negatively regulated miRNA-mRNA relationship pairs were identified. Functional analysis demonstrated that DEmRNAs in the targeted network were enriched in vascular smooth muscle contraction and focal adhesion pathways. In addition, the area under the curve of 16 hub miRNAs was >0.8. It is implied that 16 hub miRNAs may be used as potential diagnostic biomarkers of IA. CONCLUSION: Hub miRNAs and key signaling pathways were identified by bioinformatics analysis. This evidence lays the foundation for understanding the underlying molecular mechanisms of IA and provided potential therapeutic targets for the treatment of this disease.

The impact on cognitive functions of patients with pituitary adenoma before and after surgery.

Patients with pituitary adenoma have often suffered cognitive impairment. The study aims to identify the factors, and their impact, that affect the cognitive functions of pituitary adenoma patients. Seventy-six patients with pituitary adenoma were recruited, together with 76 healthy subjects as control. Patients (34 functioning and 42 non-functioning) were randomly assigned into either microscopic (n = 44) or neural endoscopic (n = 32) group. All surgeries were performed through single-nostril transsphenoidal approach under general anesthesia with endotracheal intubation. All patients were examined with cognitive assessments (CAMCOG-C and MMSE tests), tumor size, eyesight, and hormone levels before surgery. Three months after surgery, all patients were examined again to check hormone level changes by blood samples, tumor excision status via MRI, and cognitive assessments. Compared with healthy control, total score and multiple cognitive scores of CAMCOG-C and MMSE were significantly lower before surgery. There were no correlations between cognitive functions and tumor size or eyesight. Significant difference in cognitive functions was found between functioning and non-functioning pituitary adenoma patients. Significant increase in cognitive functions occurred after surgery, whereas no difference was detected between the two different surgical treatments. The hormone levels were improved significantly in patients with hormone disorders after surgery. The physical compression from tumor might not play a key role in cognitive impairment. However, hormone disorders could be a major factor to cognitive impairment. The improvement in cognitive functions is attributed to the amelioration of endocrine disorders. There were no differences between two surgical treatments.

Diagnostic Values of Serum Levels of Homocysteine and Uric Acid for Predicting Vascular Mild Cognitive Impairment in Patients with Cerebral Small Vessel Disease.

BACKGROUND This study aimed to investigate the diagnostic values of serum levels of Hcy and UA for predicting vascular mild cognitive impairment (VMCI) in patients with cerebral small vessel disease (SVD). MATERIAL AND METHODS We selected 172 cerebral SVD patients and divided them into a VMCI group and a non-VMCI group. Eighty-six healthy individuals without nervous system diseases were selected as the control group. Enzymatic cycling method was performed to detect serum Hcy and UA levels. Serum levels of folic acid (FOA) and vitamin B12 (VitB12) were detected by chemiluminescence immunoassay. Montreal cognitive assessment (MoCA) was applied to evaluate the cognitive function. The ROC curve was used to evaluate the diagnostic values of serum Hcy and UA levels for predicting VMCI. Logistic regression analysis was used to determine the possible risk factors. RESULTS Compared with the non-VMCI and control groups, serum FOA and VitB12 levels were lower and serum Hcy and UA levels were higher in the VMCI group. AUC values of serum Hcy and UA levels were 0.703 and 0.829, respectively. Serum Hcy and UA levels were negatively correlated with serum FOA and VitB12 levels, total MoCA score, and subscores on visuospatial ability and executive function, on language ability and on delayed recall, and they were positively correlated with serum cholesterol (CH) level. Serum Hcy and UA levels were indicated as risk factors for VMCI in cerebral SVD patients. CONCLUSIONS These results suggest that serum Hcy and UA levels may serve as predictive factors for VMCI in cerebral SVD patients.

The effects of cognitive intervention on cognitive impairments after intensive care unit admission.

Patients who survive critical illness commonly suffer cognitive impairments. We aimed to study the effects of cognitive intervention to treat the long-term impairments observed among different populations of intensive care unit (ICU) survivors. The results showed that the intervention significantly suppressed the deterioration of cognitive function in these patients. Medical and neurological ICU survivors were more susceptible than post-anaesthesia ICU patients to severe cognitive damage. In the former, the deterioration of impairments can be slowed by cognitive intervention. In comparison, intervention exerted significantly positive effects on the recovery of the cognitive functions of post-anaesthesia care unit patients. Furthermore, young populations were more likely than older populations to recover from acute cognitive impairments, and the impairment observed among the older population seemed to be multi-factorial and irreversible.

[Relationship between vascular stenosis and cognition in leukoaraiosis patients].

OBJECTIVE: To explore the relationship between the degree of vascular stenosis and cognition in leukoaraiosis patients. METHODS: A total of 101 leukoaraiosis patients from the Department of Neurology, The First Affiliated Hospital of Anhui Medical University between September 2013 and June 2014, divided into two groups:patients with cognitive impairment (SVCI) (n = 54) , and those without cognitive impairment (NC) (n = 47) . All patients were enrolled and examined by magnetic resonance imaging (MRI) scanning and magnetic resonance angiography (MRA) or computed tomography angiography (CTA). The cognitive assessments were made by MMSE (mini-mental state examination), CAMCOG-C (Cambridge cognitive examination-Chinese version) and CDR (clinical dementia rating). The severity of leukoaraiosis and vascular stenosis was graded by MRI and MRA/CTA scans. RESULTS: The degree of vascular stenosis group and the severity of LA in SVCI were significantly higher than NC (2.0 ± 0.8 vs1.1 ± 0.6, 2.6 ± 1.0 vs 2.0 ± 1.0; P = 0.020, P = 0.003). As white matter level aggravated, cognitive function decreased and vascular stenosis deteriorated accordingly, and the score of MMSE (25 ± 4, 24 ± 6, 22 ± 4) and CAMCOG-C (83 ± 14, 80 ± 14, 73 ± 14) has a statistical significance (P = 0.012, P = 0.014). At the same time, the negative correlation was found in LA patients between cognitive function and severity of LA (r = -0.317, P = 0.001) as well as degree of vascular stenosis (r = -0.284, P = 0.004). Multivariate Logistic regression analysis revealed that, after controlling for various factors, both severity of LA (OR = 2.025, 95% CI 1.307-3.954) and the degree of vascular stenosis (OR = 1.812, 95% CI 1.129-2.908) were risk factors for cognitive impairment in leukoaraiosis patients. CONCLUSION: Cognition of leukoaraiosis patients is correlated with both severity of leukoaraiosis and vascular stenosis.

Serum antioxidant levels associated with subcortical ischemic vascular disease.

OBJECTIVE: We aimed to examine changes in serum bilirubin and uric acid (ua) levels in subcortical ischemic vascular disease (Sivd). in addition, we investigated if altered serum bilirubin and ua levels correlate with the subtypes of Sivd as well as the severity of leukoaraiosis (la). METHODS: this cross-sectional study included 1098 consecutive patients with slight symptoms, such as dizziness, vertigo etc. according to magnetic resonance imaging (Mri) appearances, they were divided into either Sivd group or controls (Cn), and the Sivd group was further grouped in lacunar infarction (li) and la subtypes, as well as different grades. Serum bilirubin and ua levels were determined by the vanadate oxidase method and enzymatic method respectively, after at least an eight hour overnight fasting, in all subjects. RESULTS: the bilirubin level was obviously lower while the ua level was significantly higher in the Sivd group when compared with the controls. Moreover, the la subgroup presented more significant changes in bilirubin and ua when compared to the li subgroup in both males and females. the correlation was positive between the ua levels and the la severity (r=0.134, p=0.006). Multivariate regression analysis revealed that the odds ratio (95% Ci) for Sivd in the lowest tertile of total bilirubin (tbil<9.58 µmol/l) and highest tertile of ua (ua>339 µmol/l) were 2.702(1.936-3.770) and 2.135(1.521-2.996) respectively after adjusting for confounding variables. CONCLUSION: Serum bilirubin levels were lower, whereas ua levels were higher in Sivd patients when compared with controls in both males and females, especially in la patients. Moreover, serum ua levels positively correlated to la severity.

Hydrogen Sulfide Protects against Rat Ischemic Brain Injury by Promoting RhoA Phosphorylation at Serine 188.

The protective role of hydrogen sulfide against cerebral ischemia-reperfusion injury involves the inhibition of the RhoA-/Rho-associated coiled-coil kinase (ROCK) pathway. However, the specific mechanism remains elusive. This study investigates the impact of hydrogen sulfide on RhoA phosphorylation at serine 188 (Ser188) in vivo, aiming to test the hypothesis that hydrogen sulfide exerts neuroprotection by enhancing RhoA phosphorylation at Ser188, subsequently inhibiting the RhoA/ROCK pathway. Recombinant RhoAwild-pEGFP-N1 and RhoAS188A-pEGFP-N1 plasmids were constructed and administered via stereotaxic injection into the rat hippocampus. A rat global cerebral ischemia-reperfusion model was induced by bilateral carotid artery ligation to elucidate the neuroprotective mechanisms of hydrogen sulfide. Both RhoAwild-pEGFP-N1 and RhoAS188A-pEGFP-N1 plasmids expressed RhoAwild and RhoAS188A proteins, respectively, in rat hippocampal tissues, alongside the intrinsic RhoA protein. Systemic administration of the exogenous hydrogen sulfide donor sodium hydrosulfide led to an increase in Ser188 phosphorylation of transfected RhoAwild and intrinsic RhoA protein within the hippocampus. However, this effect was not observed in tissues transfected with RhoAS188A. Sodium hydrosulfide-mediated RhoA phosphorylation correlated with decreased RhoA and ROCK2 activity in rat hippocampal tissues. Furthermore, sodium hydrosulfide administration reduced cerebral ischemia-reperfusion-induced neuronal damage and apoptosis in rat hippocampal tissues transfected with RhoAwild. However, this neuroprotective effect was attenuated in rats transfected with RhoAS188A. These findings suggest that the neuroprotective mechanism of hydrogen sulfide against cerebral ischemia/reperfusion injury involves increased RhoA phosphorylation at Ser188. Promoting this phosphorylation may represent a potential intrinsic therapeutic target for ischemic stroke.

The association between alpha diversity of gut microbiota, neuroimaging markers and cognitive function in cerebral small vessel disease.

There is increasing recognition of gut microbial dysbiosis in cerebral small vessel disease (CSVD). The altered diversity in a single ecosystem - alpha diversity index of gut microbiota has attracted wide attention. Our study aims to determine whether the alpha diversity index differs among healthy control (HC), CSVD with and without cognitive impairment. Moreover, we investigate the correlation between the alpha diversity index, neuroimaging markers, and cognitive function. We recruited 40 HC, 43 CSVD patients without cognitive impairment (CSVD-NCI), and 35 CSVD patients with mild cognitive impairment (CSVD-MCI). Clinical and neuropsychological assessments, MRI scanning, and gut microbiota analysis were performed on all participants. The alpha diversity indexes Chao1 and Shannon were calculated to evaluate community richness and diversity in a sample, respectively. Individual neuroimaging markers of CSVD and the CSVD burden score were also evaluated. A significantly lower level of Chao 1 rather than the Shannon index was observed in the CSVD subgroups than in the HC group. The level of the Chao 1 index was negatively correlated with both CMB counts, a neuroimaging characteristic of CSVD, and CSVD burden score in patients with CSVD. Additionally, the Chao 1 index has been associated with general cognitive function, information processing speed, and language function in patients with CSVD. Remarkably, the increased CSVD burden score mediated the effects of decreased levels of Chao 1 on information processing speed and language function. Hence, the alterations in species richness may be associated with CSVD-related cognitive impairment and mediated by CSVD neuroimaging markers.

Synergistic effect of folate and MTHFR C677T on hippocampal subfields and perfusion in Alzheimer's disease.

BACKGROUND: Low folate intake and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism have been suggested to increase the risk of Alzheimer's disease (AD). However, the synergistic effects and their impact on brain structure and perfusion remain unclear. METHODS: This study explored the effects of dietary and genetic deficiencies in folate metabolism on the volume of the hippocampal subregions, cerebral perfusion, and cognitive decline in 71 cognitively unimpaired (CU) individuals and 102 patients with mild cognitive impairment (MCI) due to AD or AD. All participants underwent magnetic resonance imaging, laboratory examinations, and neuropsychological assessments. The hippocampal subfields were segmented using Freesurfer, and arterial spin labeling was used to measure the cerebral blood flow. RESULTS: We found a significant group-by-MTHFR interaction effect on folate. Patients with AD and the 677 T allele showed hypoperfusion in the left precuneus compared to patients without this mutation, which mediated the relationship between low folate level and cognitive decline in patients carrying the 677 T allele. Moreover, a synergistic effect was observed for the combination of decreased folate concentrations and the presence of the MTHFR 677 T allele on the atrophy of specific hippocampal subregions in patients with AD. CONCLUSIONS: In addition to offering insights into the neuronal mechanism underlying gene-dependent folate-induced cognitive impairment in AD, these findings may have clinical significance for the allocation of auxiliary folate supplementation therapy in patients with AD with low folate levels and carrying the MTHFR 677 T allele and may eventually promote the selection of early individualized AD drug therapy.

The Hippocampal Subfield Volume Reduction and Plasma Biomarker Changes in Mild Cognitive Impairment and Alzheimer's Disease.

Background: The hippocampus consists of histologically and functionally distinct subfields, which shows differential vulnerabilities to Alzheimer's disease (AD)-associated pathological changes. Objective: To investigate the atrophy patterns of the main hippocampal subfields in patients with mild cognitive impairment (MCI) and AD and the relationships among the hippocampal subfield volumes, plasma biomarkers and cognitive performance. Methods: This cross-sectional study included 119 patients stratified into three categories: normal cognition (CN; N = 40), MCI (N = 39), and AD (N = 40). AD-related plasma biomarkers were measured, including amyloid-ß (Aß)42, Aß40, Aß42/Aß40 ratio, p-tau181, and p-tau217, and the hippocampal subfield volumes were calculated using automated segmentation and volumetric procedures implemented in FreeSurfer. Results: The subiculum body, cornu ammonis (CA) 1-head, CA1-body, CA4-body, molecular_layer_HP-head, molecular_layer_HP-body, and GC-ML-DG-body volumes were smaller in the MCI group than in the CN group. The subiculum body and CA1-body volumes accurately distinguished MCI from CN (area under the curve [AUC] = 0.647-0.657). The subiculum-body, GC-ML-DG-body, CA4-body, and molecular_layer_HP-body volumes accurately distinguished AD from MCI (AUC = 0.822-0.833) and AD from CN (AUC = 0.903-0.905). The p-tau 217 level served as the best plasma indicator of AD and correlated with broader hippocampal subfield volumes. Moreover, mediation analysis demonstrated that the subiculum-body volume mediated the associations between the p-tau217 and p-tau181 levels, and the Montreal Cognitive Assessment and Auditory Verbal Learning Test recognition scores. Conclusions: Hippocampal subfields with distinctive atrophy patterns may mediate the effects of tau pathology on cognitive function. The subiculum-body may be the most clinically meaningful hippocampal subfield, which could be an effective target region for assessing disease progression.

Disrupted Dynamic Network Attribution Associated with Gait Disorder in Cerebral Small Vessel Disease.

Background and Aims: Previous research has focused on static functional connectivity in gait disorders caused by cerebral small vessel disease (CSVD), neglecting dynamic functional connections and network attribution. This study aims to investigate alterations in dynamic functional network connectivity (dFNC) and topological organization variance in CSVD-related gait disorders. Methods: A total of 85 patients with CSVD, including 41 patients with CSVD and gait disorders (CSVD-GD), 44 patients with CSVD and non-gait disorders (CSVD-NGD), and 32 healthy controls (HC), were enrolled in this study. Five networks composed of 10 independent components were selected using independent component analysis. Sliding time window and k-means clustering methods were used for dFNC analysis. The relationship between alterations in the dFNC properties and gait metrics was further assessed. Results: Three reproducible dFNC states were determined (State 1: sparsely connected, State 2: intermediate pattern, and State 3: strongly connected). CSVD-GD showed significantly higher fractional windows (FW) and mean dwell time (MDT) in State 1 compared with CSVD-NGD. Higher local efficiency variance was observed in the CSVD-GD group compared with HC, but no differences were found in the global efficiency comparison. Both the FW and MDT in State 1 were negatively correlated with gait speed and step length, and the relationship between MDT of State 1 and gait speed was mediated by overall cognition, information processing speed, and executive function. Conclusions: Our study uncovered abnormal dFNC indicators and variations in topological organization in CSVD-GD, offering potential early prediction indicators and freshening insights into the underlying pathogenesis of gait disturbances in CSVD.

[Changes of serum bilirubin and uric acid in patients with myasthenia gravis].

OBJECTIVE: To explore the correlations of serum total bilirubin (TBIL), direct bilirubin (DBIL), indirect bilirubin (IBIL) and uric acid (UA) with myasthenia gravis (MG). METHODS: A total of 131 MG patients were selected as MG group and 176 healthy cases as control group. They were enrolled from the Department of Neurology, First Affiliated Hospital, Anhui Medical University between January 2010 and December 2012. And the controls were recruited from a health check-up center. The total serum BIL and UA concentrations were measured by an enzymatic method. All MG patients underwent thymus computed tomography (CT) scanning. RESULTS: The serum levels of TBIL, IBIL and UA in patients with MG ((11.0 ± 0.4, 7.4 ± 0.3, 270 ± 70) µmol/L) were significantly lower than those in healthy control group ((13.0 ± 0.4, 9.6 ± 0.3, 301 ± 60) µmol/L) (P < 0.01). Moreover, these results were consistent when the male and female cohorts were investigated separately. In MG group, females had significantly lower serum TBIL, IBIL and UA levels ( (10.1 ± 3.7, 6.7 ± 2.7, 242 ± 68) µmol/L) than males ((12.2 ± 5.5, 8.4 ± 4.2, 288 ± 73) µmol/L) (P < 0.05-0.01). However, no difference existed when comparing different grades of MG patients according to the modified Osserman classification. Also no significant difference existed between MG patients with thymic abnormalities and those without. In comparison with the subjects in the reference group (total bilirubin ≥ 11.4 µmol/L, UA ≥ 279 µmol/L), the odds ratio (95% CI) for MG patients in the lower tertile (total bilirubin < 11.4 µmol/L, UA < 279 µmol/L) were 1.98 (1.20-3.29) and 2.22 (1.29-3.82) respectively after multivariable adjustment. Serum level of TBIL and UA had positive correlations with creatinine as indicated by Pearson correlation analysis (r = 0.151, P = 0.008; r = 0.301, P = 0.000). Meanwhile, serum level of UA had a negative correlation with high density lipoprotein-cholesterol (r = -0.347, P = 0.000) . CONCLUSION: Decreased serum levels of BIL and UA are closely correlated with MG. As a replacement therapy, administration of BIL and UA or theirs precursors may offer benefits to the MG patients.

[Influence of leukoaraiosis on the cognition of patients with Parkinson disease].

OBJECTIVE: To explore the role of leukoaraiosis (LA) on the cognitive function in patients with Parkinson disease (PD). METHODS: The cohort for this study included 63 patients with PD, whom were divided into 3 groups according to cognitive status:with intact cognition (PD-IC, n = 23), with mild cognitive impairment (PD-MCI, n = 23) and with dementia (PDD, n = 17). All the patients were recruited from the Department of Neurology, First Affiliated Hospital, Anhui Medical University between September 2011 and July 2012. The cognitive functions were evaluated by mini-metal state examination (MMSE), the Cambridge cognitive examination-Chinese version (CAMCOG-C), clinical dementia rating (CDR), clock drawing task (CDT) and verbal fluency test, etc. Depression symptoms were assessed by the geriatric depression scale (GDS) while motor symptoms by the Unified Parkinson's Disease Rating Scale-motor (UPDRS-motor) and the Hoehn and Yahr scale (HY). All the patients underwent magnetic resonance imaging (MRI) with a 3.0-T system. LA was rated using the semiquantitative visual rating system proposed by scheltens et al. RESULTS: Both the PD-IC (2.43 ± 2.79) and PD-MCI (4.48 ± 4.33) groups showed significantly lower deep hyperintensities (DHs) scores than the PDD group (7.88 ± 6.69, P = 0.004 and 0.040, respectively), especially in frontal (1.09 ± 1.31; 1.83 ± 1.90; 3.24 ± 2.64, P < 0.05) and parietal areas (0.09 ± 0.29; 0.65 ± 1.03; 1.53 ± 2.32, P < 0.05). There were no significant differences in periventricular (1.57 ± 1.75; 2.52 ± 2.37; 3.24 ± 2.64, P > 0.05), basal ganglia (0.09 ± 0.42; 0.30 ± 0.77; 0.53 ± 1.33, P > 0.05) and infratentorial white matter hyperintensities scores (--; 0.13 ± 0.63; 0.18 ± 0.73, P > 0.05) among three groups. The DHs showed a significant correlation with age (P = 0.003), MMSE (P = 0.009), verbal fluency test (P = 0.009), orientation (P = 0.047) and executive function (P = 0.027) in CAMCOG-C. The multiple regression analysis showed that the MMSE scores were associated significantly with education (P < 0.001, ß = 0.600), DHs (P = 0.001, ß = -0.678) and HY (P = 0.035, ß = -0.480). DHs were the most significantly associated with MMSE scores. CONCLUSION: There was a significant correlation between DHs and multiple domain cognitive impairment in PD, especially in executive function. DHs, which were the most significantly variable associated with MMSE scores, may contribute to cognitive impairment in PD.

Identification of immune-related molecular markers in intracranial aneurysm (IA) based on machine learning and cytoscape-cytohubba plug-in.

BACKGROUND: Intracranial aneurysm (IA) is a common cerebrovascular disease. The immune mechanism of IA is more complicated, and it is unclear so far. Therefore, it is necessary to continue to explore the immune related molecular mechanism of IA. METHODS: All data were downloaded from the public database. Limma package and ssGSEA algorithm was used to identify differentially expressed mRNAs (DEmRNAs) and analyze immune cell infiltration, respectively. Machine learning and cytoscape-cytohubba plug-in was used to identify key immune types and multicentric DEmRNAs of IA, respectively. Multicentric DEmRNAs related to key immune cells were screened out as key DEmRNAs by Spearman correlation analysis. Diagnostic models, competing endogenous RNA (ceRNA) regulatory network and transcription factor regulatory network were constructed based on key DEmRNAs. Meanwhile, drugs related to key DEmRNAs were screened out based on DGIdb database. The expression of key DEmRNAs was also verified by real time-PCR. RESULTS: In this study, 7 key DEmRNAs (NRXN1, GRIA2, SLC1A2, SLC17A7, IL6, VEGFA and SYP) associated with key differential immune cell infiltration (CD56bright natural killer cell, Immature B cell and Type 1 T helper cell) were identified. Functional enrichment analysis showed that VEGFA and IL6 may be involved in the regulation of the PI3K-Akt signaling pathway. Moreover, IL6 was also found to be enriched in cytokine-cytokine receptor interaction signaling pathway. In the ceRNA regulatory network, a large number of miRNAs and lncRNAs were found. In the transcription factor regulatory network, the transcription factor SP1 was correlated with VEGFA, SYP and IL6. It is also predicted that drugs related to key DEmRNAs such as CARBOPLATIN, FENTANYL and CILOSTAZOL may contribute to the treatment of IA. In addition, it was also found that SVM and RF models based on key DEmRNAs may be potential markers for diagnosing IA and unruptured intracranial aneurysm (UIA), respectively. The expression trend of key DEmRNAs verified by real-time PCR was consistent with the bioinformatics analysis results. CONCLUSION: The identification of molecules and pathways in this study provides a theoretical basis for understanding the immune related molecular mechanism of IA. Meanwhile, the drug prediction and diagnosis model construction may also be helpful for clinical diagnosis and management.

Serum Cystatin C is Associated with Depression After Intracerebral Hemorrhage.

Purpose: Cystatins are associated with neuronal degeneration and nervous system healing. Cystatin C (Cys C) has recently been linked to brain injury and immunological inflammation. This study aimed to determine the relationship between serum Cys C levels and depression following intracranial hemorrhage (ICH). Patients and Methods: Between September 2020 and December 2022, 337 patients with ICH were sequentially recruited and followed up for three months. The post-stroke depression (PSD) and non-PSD groups were separated based on the 17-item Hamilton Depression Rating Scale (HAMD). The PSD diagnosis was established based on the DSM-IV criteria. Cys-C levels were documented within twenty-four hours of admission. Results: Three months after ICH, 93 (27.6%) of 337 enrolled patients were diagnosed with depression. The Cys C levels were significantly higher in depressed patients than in nondepressed patients after ICH (1.32 vs 1.01; p<0.001). After adjusting for potential confounding variables, depression after ICH was associated with the highest quartile of Cys C levels (odds ratio (OR) = 3.195, 95% CI: 1.562-6.536; p=0.001). The receiver operating characteristic curve (ROC) curve predicted that the ideal cut-off for CysC levels as a predictor of depression after ICH would be 0.730, resulting in 84.5% sensitivity and 88.4% specificity, with an area under curve (AUC) of 0.880 (95% CI: 0.843-0.917; p< 0.0001). Conclusion: Increased CysC concentrations were independently related to depression three months after ICH, highlighting that CysC levels at admission may be a potential biomarker for predicting the onset of depression following ICH.