bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association between beta amyloid plaque deposition and neuronal activity measured by Resting‐state fMRI in Alzheimer’s Disease and mild cognitive impairment
Authors: Haddad Seyyed M. H. , Soddu Andrea , Menon Ravi S. , Bartha Robert 
Published: June 2023

AbstractBackgroundDespite the important role of amyloid‐beta protein (Aβ) in the initiation and progression of Alzheimer’s Disease (AD), the precise mechanism by which Aβ disrupts neuronal activity (NA) and structure during disease development, and whether this protein is an appropriate therapeutic target is still controversial. Recently, we introduced several novel NA metrics (Kazemeifar, PLoS One 2017; Haddad, ISMRM 2019) based on specific spatiotemporal features of the resting‐state fMRI (rs‐fMRI) signal. These NA metrics are significantly lower in AD and mild cognitive impairment (MCI) compared to normal elderly controls. Here, we examine whether there is an association between resting‐state fMRI NA levels and Aβ deposition in grey matter (GM) measured by PET in AD and MCI.Method[18F]florbetapir Aβ PET images and rs‐fMRI data (TR = 3s, 197 volumes) in 9 participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI, 3 early MCI (EMCI), 3 MCI, and 3 AD, aged 77 ± 7 years, 3 females) were included. The rs‐fMRI data was pre‐processed and decomposed into independent components (ICs) using IC analysis. The ICs associated with neuronal activity were identified using a support vector machine classifier (Demertzi, Cortex 2014). NA was quantified in each voxel using the magnitude of the neuronal ICs in the rs‐fMRI signal. This magnitude was calculated based on similarity (cross‐covariance) between each neuronal IC and rs‐fMRI signal (Haddad, ISMRM 2019). In each subject, the pre‐processed PET images (Jagust, Alzheimers. Dement. 2015) were registered to the T1‐weighted image to which the NA maps were already registered. GM voxelwise correlation was then conducted between the NA and [18F]florbetapir uptake maps in each subject.ResultThe NA and [18F]florbetapir uptake maps in one EMCI subject (Figure 1) and related scatter plot (Figure 2) show the correlation between NA and [18F]florbetapir uptake in GM. In all subjects studied, NA and [18F]florbetapir uptake were significantly negatively correlated (r = ‐0.25 ± 0.14) (Table 1).ConclusionThe negative correlation between NA and [18F]florbetapir uptake in this preliminary study indicates that Aβ deposition contributes to decreased neuronal activity in AD and MCI measured by rs‐fMRI. Future studies should determine the susceptibility of various brain regions to Aβ accumulation.
Abnormal gamma frequency phase‐amplitude coupling associated with network hyperexcitability in Alzheimer’s Disease
Authors: Prabhu Pooja , Ranasinghe Kamalini G , Morise Hirofumi , Kudo Kiwamu , Hinkley Leighton B , Lerner Hannah M , Mizuiri Danielle , Licata Abigail , Kotegar Karunakar A , Findlay Anne , Miller Bruce L , Gorno‐Tempini Marilu , Kramer Joel H. , Rankin Katherine P , Garcia Paul , Kirsch Heidi , Houde John F , Vossel Keith , Nagarajan Srikantan S 
Published: June 2023

AbstractBackgroundAlzheimer’s disease (AD) carries an increased risk of seizures and subclinical epileptiform activity (Vossel et al. 2016). Network hyperexcitability which is the underlying phenomenon of epileptic manifestations is thought to contribute to AD pathophysiological processes. Recently we demonstrated that greater degree of neural synchronization deficits within 2‐8Hz range of frequency oscillations are sensitive indicators of network hyperexcitability (Ranasinghe et al. 2021). Here, we sought to examine the high frequency gamma band deficits associated with network hyperexcitability in AD patients.MethodsSpecifically, we quantified Phase Amplitude Coupling (PAC) between the amplitude of gamma oscillations (30‐40Hz); with the phase of 2‐8Hz oscillations) (Figure 1). We used 60s resting‐state magnetoencephalography (MEG) recordings from 48 AD patients (n = 22, with subclinical epileptiform activity, AD‐EPI+; n = 28 without subclinical epileptiform activity, AD‐EPI‐), and 35 age‐matched controls. We computed PAC for each of 68 cortical regions (Desikan et al. 2006) on source‐space reconstructed MEG signal using the mean vector length (Canolty et al. 2006).ResultsPermutation cluster test was performed for statistical comparisons between AD patients vs. age matched controls, and AD‐EPI+ vs. AD‐EPI‐. Patients with AD showed significantly higher theta (4‐8 Hz)‐gamma coupling in the left parahippocampal and right caudal‐middle frontal regions. Importantly, this increased left parahippocampal theta‐gamma coupling was significantly higher in AD‐EPI+ patients than in AD‐EPI‐. AD‐EPI+ also showed higher alpha (8‐12Hz)‐gamma coupling in the right parahippocampal region compared to AD‐EPI‐ (Figure 2).ConclusionThese results not only identify gamma band coupling deficits specifically localized to medial temporal regions which are the earliest affected regions in AD pathophysiology but also delineate the associated vulnerabilities of network hyperexcitability in AD.
Amyloid accumulation in the medial temporal area starts in the mild cognitive impairment stage of Alzheimer’s disease in [18F]flutemetamol positron emission tomography
Authors: Imabayashi Etsuko , Ishii Kenji , Toyohara Jun , Kojima Narumi , Tago Tetsuro , Sakata Muneyuki , Wagatsuma Kei , Ishibashi Kenji , Tokumaru Aya M. , Kim Hunkyung 
Published: June 2023

AbstractBackgroundThis study was aimed to evaluate the hierarchical accumulation of amyloid in the Alzheimer’s brain according to clinical stage using [18F]flutemetamol positron emission tomography.MethodThis was a prospective, single‐cohort study of volunteers who lived independently in Itabashi‐ku (Tokyo, Japan). One hundred thirty‐six participants (female/male = 96/40, mean age/standard deviation = 79.2/4.0 years) were recruited. Two subjects, one with meningeal thickening and another with sequelae in the brain, and 17 visually amyloid‐negative MCI subjects who possibly had neurodegenerative disease other than Alzheimer’s disease were excluded from the further analysis. We applied voxel‐based regression slope analysis using composite voxel of interest values calculated with Cortex ID Suite (GE Healthcare) and [18F]flutemetamol positron emission tomography images in three groups: 70 amyloid‐negative cognitively normal (CN) participants, 29 amyloid‐positive cognitively normal (PreC) participants, and 18 amyloid‐positive MCI (MCI+) participants. Statistical Parametric Mapping 12 software was used for analysis.ResultCompared with the CN group, the PreC group showed accelerated amyloid accumulation in a wide area, except for the medial temporal lobe, paracentral sulcus, and medial occipital lobe. In amyloid‐positive subjects, amyloid accumulation was quicker in the paracentral sulcus, occipital cortex, and left medial temporal lobe in the MCI+ group than in the PreC group. Additional voxel of interest analyses were applied to the statistically significant areas. In the right posterior cingulate area, there was no significant difference between the PreC and MCI+ groups; however, the PreC and MCI+ groups showed a significantly quicker amyloid accumulation than the CN group. In contrast, in the left medial temporal area, the increase of amyloid accumulation was greater only in the MCI+ group compared to the PreC and CN groups.ConclusionIn amyloid‐positive subjects, amyloid accumulation in the left medial temporal lobe did not increase in the preclinical stage. In the medial temporal and occipital lobes, which are relatively spared from amyloid accumulation, it is considered to start late in the MCI stage and not in the preclinical stage. Further study of volume and other biomarkers is requreid to evaluate the regional pathophysiological variability of AD.
Increased white matter hyperintensity burden on MRI in autosomal dominant familial compared to young onset sporadic Alzheimer’s disease.
Authors: Accorroni Alice , Fraser Maggie R , Walsh Phoebe , O'Connor Antoinette , Cardoso M Jorge , Fox Nick C , Sudre Carole H , Ryan Natalie S 
Published: June 2023

AbstractBackgroundWhite matter hyperintensities (WMH) on MRI may be observed in familial and sporadic AD. However, studies comparing WMH burden between these two groups are lacking. We conducted this study to evaluate the load and distribution of WMH in individuals with autosomal dominant familial Alzheimer’s disease (FAD) and young onset sporadic AD (SAD), their relationship to grey matter volumes and to neuropsychological test scores (NPT).MethodIn this cross‐sectional study, we evaluated global and local differences in WMH severity on MRI in 19 individuals with symptomatic FAD due to Presenilin 1 mutations, 20 individuals with young onset SAD and 19 healthy control subjects, controlling for age, cerebrovascular risk (CVR) and APOEε4 carrier status. Relationships between WMH, grey matter (GM) volumes and NPT were also investigated.ResultThe FAD group had higher WMH load in all the areas considered apart from juxta‐cortical and periventricular layers when compared to the SAD group. The two groups were well matched for disease duration and severity of cognitive impairment as assessed by the MMSE. APOEε4 genotype and cardiovascular risk factors acted as negative confounders in the identified differences in WMH volumes. There was no association between WMH and GM volumes or NPT in either AD group.ConclusionDespite their young age and minimal CVR, the FAD group in this study had a higher load of WMH compared to the SAD group, suggesting that WMH may reflect aspects of AD pathology that are particularly prominent in FAD. Our analysis suggests that APOEε4 genotype and cardiovascular risk factors may have a greater influence on WMH burden in SAD than in FAD. Furthermore, we did not identify a correlation between WMH load and GM volumes in either group, suggesting that WMH are not merely correlates of GM pathology in AD but may represent independent features of the disease.
Degradation of Oligomer Tau by Autophagy
Authors: Imai Miku , Hamano Tadanori , Sasaki Hirohito 
Published: June 2023

AbstractBackgroundThe specific pathological findings in Alzheimer’s disease (AD) brain are senile plaques composed of amyloid‐β protein (Aβ) and neurofibrillary tangles (NFTs) composed of highly phosphorylated tau protein. It has been suggested that autophagy may play an important role in the degradation of tau proteins. In this study, we investigated whether autophagy is involved in the degradation of oligomeric tau by immunohistochemistry using autopsied AD brains.MethodFrozen brains were homogenized to produce lysates, and Western blotting (WB) was performed using anti‐LC3 antibody, a marker of autophagy. The parietal lobes of the same autopsy brains were used for immunohistochemical analysis using anti‐LC3, anti‐P62, anti‐oligomeric tau antibody (TOC‐1) and anti‐phosphorylated tau antibody (PHF‐1).ResultIn the WB of the temporal lobe, LC3‐II was generally increased in AD brains compared to controls. In addition, immunostaining showed that oligomeric tau (TOC1) and LC3 coexisted in AD brains. In AD and control brains, phosphorylated tau, which stained faintly, was found to coexist with LC3, but LC3 was not found in the cytoplasm of neurons with serious phosphorylated tau (PHF‐1) deposition. However, the coexistence of highly phosphorylated tau and p62 was remarkable. No LC3 or P62 staining was observed in the neuropil thread.ConclusionThese results suggest that oligomeric tau is degraded by autophagy and phosphorylated tau is also degraded by autophagy, but autophagy may no longer function when the degree of phosphorylated tau deposition is serious.
Brain regional alternative splicing and clinical traits in Alzheimer’s disease
Authors: Kim Sara , Han Seonggyun , Nho Kwangsik , LEE YOUNGHEE , Koh Insong 
Published: June 2023

AbstractBackgroundAlzheimer’s disease (AD) is one of the most complex diseases and is characterized by neuropathological features, including accumulation of beta‐amyloid plaques and tau neurofibrillary tangles. These neuropathological features exhibit heterogeneity across brain regions in different patients, leading to different symptoms. Dysregulation of alternative splicing (AS) has been observed to contribute to neuropathological features in AD; however, their molecular mechanisms via AS remain unclear. Therefore, we aimed to systemically investigate the impact of AS (i.e., exon skipping) on AD‐related neuropathological features (i.e., Braak stage and plaque density) and the functional connections of alternately spliced genes across multiple brain regions in AD patients.MethodWe analyzed RNA‐seq data generated by the MSBB project representing two brain regions: the frontal region (frontal pole; FP, n = 175, inferior frontal gyrus; IF, n = 87) and the temporal (parahippocampal gyrus; PH, n = 93 and superior temporal gyrus; ST, n = 101). The data were mapped to the hg19 reference genome with the STAR aligner and exon skipping rates were estimated as percent spliced in (PSI) by rMATs. Then, we performed a linear regression to evaluate clinical or pathogenic associations between exon PSI levels and the Braak stage and plaque density mean for each brain region, considering sex as a covariate.ResultWe identified 192 and 158 exon skipping (ES) associated with Braak stages in the frontal and temporal regions, respectively. In addition, 863 and 845 events were associated with plaque density. Notably, while the two regions shared only 20% (60 events) of Braak‐associated ES, they coincided in 90% (808 events) of plaque‐associated ES. Enrichment analysis of functional annotations found that frontal‐specific ES associated with Braak stage was enriched in interleukin signaling and the neurodegenerative‐related CDK5 pathway, while temporal‐specific ES was enriched in lipoprotein clearance functional pathways. For plaque density‐associated ES shared between regions, the most significantly enriched pathway was Notch4 signaling, represented for example by SOD2, in which skipping of the functional domain‐encoding exon 4 was associated with plaque mean in both regions.ConclusionThis study provides a landscape of brain region‐dependent AS events and of AD risk genes that contribute to neuropathological features in AD patients.
Rapid and economic method to measure chocolate viscosity
Authors: Monteiro Luciana , Cooney Joseph , Martini Silvana 
Published: June 2023

AbstractThe objective of this research was to use simple and economic techniques to measure chocolate viscosity and compare the values with the ones obtained using a rheometer. Two techniques were used: (a) Zahn cup number 5, and (b) ring/spread test using a ring and a template with concentric circles (ring method). Seven chocolates with a wide range of viscosities were used: (a) three 70% dark chocolates; (b) 70% dark chocolate with 1% lecithin added; (c) 70% dark chocolate with 10% cocoa butter added; (d) a Swiss‐style milk chocolate; (e) a 50% milk chocolate. Results from this research showed that the viscosity obtained using the Zahn cups was positively correlated with the Casson plastic viscosity (r = 0.897; p = 0.016) while the values obtained using the ring/spread method were negatively correlated with the Casson yield stress (r = −0.916; p = 0.004) and the Casson plastic viscosity (r = −0.897; p = 0.007). These results are helpful for small producers of chocolate that need to quantify the viscosity of their product using simple and economic techniques.
A DFT mechanistic study on the N‐acyloxyamine‐initiated controlled degradation of polypropylene
Authors: Yu Fang , Ma Tian , Liang Wenbin , Lei Ming 
Published: June 2023

AbstractN‐acyloxyamine is an excellent radical initiator for the controlled degradation of polypropylene (PP). Irgatec CR 76 (CR‐76) is one of the most important N‐acyloxyamines for the controlled degradation processes. The experiments show that 2 wt% CR‐76 caused a degradation and lowering of Mw to over 50% and of Mn in 10%–15%. The density functional theory (DFT) calculated results indicate that the NO bond cleavage of enol‐CR‐76 is the easiest to generate nitrogen (N˙) and ˙CH2COO radicals. In the controlled degradation process of PP, compared with the generated nitrogen (N˙), nitroxyl (NO˙), and nitrogen peroxide (NOO˙) radicals, the produced small molecule radicals such as CH3COO˙, (CH3)2CH˙, and (CH3)2CHCH2˙ radicals show better activity in the hydrogen abstraction process of PP. In addition, the NO˙, NOO˙, and ROO˙ (R = (CH3)2CH) radicals were proposed to be of importance in the radical coupling and β‐scission of PP˙ radical after the hydrogen abstraction in the controlled degradation of PP. This provide new insights into the controlled degradation of PP. Furthermore, thereby some theoretical guidance could be provided into the design of new N‐acyloxyamine radical initiator for the controlled degradation of polymers.
Thermal‐Responsive Liquid Crystal Elastomer Foam‐based Compressible and Omnidirectional Gripper
Authors: Zhang Xinyuhang , Liao Wei , Wang Yunpeng , Yang Zhongqiang 
Published: June 2023

AbstractLiquid crystal elastomers (LCEs) are considered to be a promising material for the fabrication of soft grippers because of their large and reversible deformations, an LCE gripper with suitable compressibility and omnidirectionality has not yet been developed. To overcome these obstacles, this study utilizes salt template method to fabricate a rod‐like LCE foam as gripper. The thickness of the compressible foam can be reduced by up to 77%, temporarily maintaining the deformation and enabling the gripper to pass through slits. The foam was aligned along the long axis and the length of the foam exhibits reversible thermal responsiveness and contract up to 57% along its alignment. Additionally, when the foam approaches a heat source, the generated temperature gradient results in a contraction gradient owing to the low thermal conductivity of the LCE foam. This in turn causes the foam to reversibly bend with a bending angle up to 93° and follow the movement of a heat source omnidirectionally. The developed gripper successfully grasps, moves, and releases hot objects in a cold and safe place, demonstrating its potential for emergency disposal. Thus, LCE foams can be considered suitable materials for novel gripper design and construction.
Mureneinwirkungen auf Massivbrückenüberbauten
Authors: Friedl Caroline , Wernhart Susanna , Scheidl Christian , Proske Dirk 
Published: June 2023

AbstractBrückenbauwerke im alpinen Raum unterliegen verschiedenen Naturgefahren. Dazu zählen auch Muren. Murenereignisse führen nachweisbar auch zur Zerstörung von Brücken. Um Brücken für solche Einwirkungen zu bemessen, sind Angaben zur Anprallkraft von Muren notwendig. Für Murenanpralle gegen Pfeiler liegen umfangreiche, sowohl miniaturisierte als auch Realgrößenversuche vor. Für Brückenüberbauten sind bisher keine solchen Versuche bekannt. In diesem Beitrag werden miniaturisierte Murenanprallversuche an Massivbrückenquerschnitten vorgestellt. Basierend auf den Versuchsergebnissen werden Empfehlungen für die Bemessung von Massivbrücken in exponierten Lagen gegeben.
Video game addiction in psychiatric adolescent population: A hospital‐based study on the role of individualism from South China
Authors: Zhou Rui , Xiao Xing‐Yu , Huang Wen‐Jun , Wang Fei , Shen Xiao‐Qing , Jia Fu‐Jun , Hou Cai‐Lan 
Published: June 2023

AbstractBackgroundFor decades, video game‐related behaviors have been investigated in different psychologic research, much of whose attention has been paid to video game addiction (VGA), while the differences between VGA and social media addiction (SMA) should have deserved more attention. In addition to detecting common risk factors of VGA, one core question is whether social inclination (individualism or collectivism) matters.ObjectThe objectives of this study were to clarify the prevalence of VGA and SMA,, identify the influencing factors of VGA, and clarify the relationships between VGA and adolescents’ individualism–collectivism inclination.MethodThe survey was conducted among 110 adolescent psychiatric patients. For each interviewee, psychological scales were filled face to face. Path analysis was used to examine the causation structure of the childhood trauma‐related symptoms.ResultThe prevalence of VGA was 40.9% (45 out of 110), and it was 41.8% for SMA (46 out of 110); childhood trauma, social media addiction, the individualistic inclination, and the rate of homosexuality were observed to be independent indicators for video game addiction (r2 = 0.46).ConclusionPsychological counseling on patients’ internet‐related behaviors may focus on the individualistic personality and possible childhood trauma, which are two important risk factors of video game addiction. It is recommended to distinguish between video game addiction and social addiction in clinical practice.
Risk factors of postoperative bile leakage after liver resection: A systematic review and meta‐analysis
Authors: Xue Shuai , Wang Haichuan , Chen Xiangzheng , Zeng Yong 
Published: June 2023

AbstractObjectivePostoperative bile leakage (POBL) is one of the most common complications after liver resection. However, current studies on the risk factors for POBL and their impacts on surgical outcomes need to be more consistent. This study aims to conduct a meta‐analysis to analyze the risk factors for POBL after hepatectomy.MethodsWe incorporated all eligible studies from Embase, PubMed, and the Web of Science database (until July 2022) into this study. RevMan and STATA software were used to analyze the extracted data.ResultsA total of 39 studies, including 43,824 patients, were included in this meta‐analysis. We found that gender, partial hepatectomy, repeat of hepatectomy, extended hepatectomy, abdominal drain, diabetes, Child≥B, solitary tumor, and chemotherapy are the factors of grade B and C POBL. Some recognized risk factors were considered potential risk factors for grade B and C bile leakage because no subgroup analysis was performed, like HCC, cholangiocarcinoma, major resection, posterior sectionectomy, bi‐segmentectomy, S4 involved, S8 involved, central hepatectomy, and bile duct resection/reconstruction. Meanwhile, cirrhosis, benign diseases, left hepatectomy, and Segment 1 resection were not significant for grade B and C bile leakage. The influence of lateral sectionectomy, anterior sectionectomy, S1 involved, S3 involved, high‐risk procedure, laparoscope, and blood loss>1000 mL on POBL of ISGLS needs further research. Meanwhile, POBL significantly influenced overall survival (OS) after liver resection.ConclusionsWe identified several risk factors for POBL after hepatectomy, which could prompt the clinician to decrease POBL rates and make more beneficial decisions for patients who underwent the hepatectomy.