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1.
Neuroimage ; 288: 120524, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38278428

RESUMO

BACKGROUND: Arterial pulsation has been suggested as a key driver of paravascular cerebrospinal fluid flow, which is the foundation of glymphatic clearance. However, whether intracranial arterial pulsatility is associated with glymphatic markers in humans has not yet been studied. METHODS: Seventy-three community participants were enrolled in the study. 4D phase-contrast magnetic resonance imaging (MRI) was used to quantify the hemodynamic parameters including flow pulsatility index (PIflow) and area pulsatility index (PIarea) from 13 major intracerebral arterial segments. Three presumed neuroimaging markers of the glymphatic system were measured: including dilation of perivascular space (PVS), diffusivity along the perivascular space (ALPS), and volume fraction of free water (FW) in white matter. We explored the relationships between PIarea, PIflow, and the presumed glymphatic markers, controlling for related covariates. RESULTS: PIflow in the internal carotid artery (ICA) C2 segment (OR, 1.05; 95 % CI, 1.01-1.10, per 0.01 increase in PI) and C4 segment (OR, 1.05; 95 % CI, 1.01-1.09) was positively associated with the dilation of basal ganglia PVS, and PIflow in the ICA C4 segment (OR, 1.06, 95 % CI, 1.02-1.10) was correlated with the dilation of PVS in the white matter. ALPS was associated with PIflow in the basilar artery (ß, -0.273, p, 0.046) and PIarea in the ICA C2 (ß, -0.239, p, 0.041) and C7 segments (ß, -0.238, p, 0.037). CONCLUSIONS: Intracranial arterial pulsatility was associated with presumed neuroimaging markers of the glymphatic system, but the results were not consistent across different markers. Further studies are warranted to confirm these findings.


Assuntos
Sistema Glinfático , Substância Branca , Humanos , Sistema Glinfático/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Hemodinâmica
2.
Anal Chem ; 96(8): 3645-3654, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38356334

RESUMO

Accurate measurement of cancer markers in urine is a convenient method for tumor monitoring. However, the concentration of cancer markers in urine is so low that it is difficult to achieve their measurement. Photoelectrochemical (PEC) sensors are a promising technology to realize the detection of trace cancer markers due to their high sensitivity. Currently, the interference of nonspecific biomolecules in urine is the main reason affecting the high sensitivity and selectivity of PEC sensors in detecting cancer markers. In this work, a strategy of oxygen vacancy (OV) modulation is proposed to construct a fouling-resistant PEC aptamer sensing platform for the detection of α-fetoprotein (AFP), a liver cancer marker. The introduction of OVs induces the formation of intermediate localized states in the photoelectric material, which not only facilitates the separation of photogenerated carriers but also leads to the redshift of the light absorption edge. More importantly, OVs with positive electrical properties can be employed to modify the antifouling layer (C-PEG) with negatively charged groups through an electrostatic interaction. The synergistic effect of OVs, antifouling layer, and aptamer resulted in a TiO2/OVs/C-PEG-based PEC sensor achieves a wide linear range from 1 pg/mL to 100 ng/mL and a low detection limit of 0.3 pg/mL for AFP. In addition, the sensor successfully realized the determination of AFP in urine samples and accurately differentiated between normal people and liver cancer patients in the early and advanced stages. This project is of great significance in advancing the application of photoelectrochemical bioanalytical technology to achieve the detection of cancer markers in urine by investigating the construction of an OVs-regulated fouling-resistant sensing interface.


Assuntos
Incrustação Biológica , Técnicas Biossensoriais , Neoplasias Hepáticas , Humanos , alfa-Fetoproteínas , Oxigênio , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Limite de Detecção
3.
Hum Brain Mapp ; 45(5): e26634, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38553856

RESUMO

Cerebral small vessel disease (SVD) can disrupt the global brain network and lead to cognitive impairment. Conversely, cognitive reserve (CR) can improve one's cognitive ability to handle damaging effects like SVD, partly by optimizing the brain network's organization. Understanding how SVD and CR collectively influence brain networks could be instrumental in preventing cognitive impairment. Recently, brain redundancy has emerged as a critical network protective metric, providing a nuanced perspective of changes in network organization. However, it remains unclear how SVD and CR affect global redundancy and subsequently cognitive function. Here, we included 121 community-dwelling participants who underwent neuropsychological assessments and a multimodal MRI examination. We visually examined common SVD imaging markers and assessed lifespan CR using the Cognitive Reserve Index Questionnaire. We quantified the global redundancy index (RI) based on the dynamic functional connectome. We then conducted multiple linear regressions to explore the specific cognitive domains related to RI and the associations of RI with SVD and CR. We also conducted mediation analyses to explore whether RI mediated the relationships between SVD, CR, and cognition. We found negative correlations of RI with the presence of microbleeds (MBs) and the SVD total score, and a positive correlation of RI with leisure activity-related CR (CRI-leisure). RI was positively correlated with memory and fully mediated the relationships between the MBs, CRI-leisure, and memory. Our study highlights the potential benefits of promoting leisure activities and keeping brain redundancy for memory preservation in older adults, especially those with SVD.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Disfunção Cognitiva , Reserva Cognitiva , Humanos , Idoso , Pessoa de Meia-Idade , Cognição , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/psicologia , Imageamento por Ressonância Magnética , Doenças de Pequenos Vasos Cerebrais/complicações
4.
J Magn Reson Imaging ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329184

RESUMO

BACKGROUND: Vascular degeneration is an important cause of brain damage in aging. Assessing the functional properties of the cerebral vascular system may aid early diagnosis and prevention. PURPOSE: To investigate the relationships between potential vascular functional markers and vascular risks, brain parenchymal damage, and cognition. STUDY TYPE: Retrospective. SUBJECTS: Two hundred two general community subjects (42-80 years, males/females: 127/75). FIELD STRENGTH/SEQUENCE: 3 T, spin echo T1W/T2W/FLAIR, resting-state functional MRI with an echo-planar sequence (rsfMRI), pseudo-continuous arterial spin labeling (pCASL) with a three-dimensional gradient-spin echo sequence. ASSESSMENT: Cerebral blood flow (CBF) in gray matter calculated using pCASL, blood transit times calculated using rsfMRI, and the SD of internal carotid arteries signal (ICAstd ) calculated using rsfMRI; visual assessment for lacunes; quantification of white matter hyperintensity volume; permutation test for quality control; collection of demographic and clinical data, Montreal Cognitive Assessment, Mini-Mental State Examination. STATISTICAL TESTS: Kolmogorov-Smirnov test; Spearman rank correlation analysis; Multivariable linear regression analysis controlling for covariates; The level of statistical significance was set at P < 0.05. RESULTS: Age was negatively associated with ICAstd (ß = -0.180). Diabetes was associated with longer blood transit time from large arteries to capillary bed (ß = 0.185, adjusted for age, sex, and intracranial volume). Larger ICAstd was associated with less presence of lacunes (odds ratio: 0.418, adjusted for age and sex). Higher gray matter CBF (ß = 0.154) and larger ICAstd (ß = 0.136) were associated with better MoCA scores (adjusted for age, sex, and education). DATA CONCLUSION: Prolonged blood transit time, decreased ICAstd , and diminished CBF were associated with vascular dysfunction and cognitive impairment. They may serve as vascular functional markers in future studies. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.

5.
Chem Biodivers ; 21(2): e202301684, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38224313

RESUMO

To develop new chemicals that are stable at high temperatures with biological activity, a pyrrole intermediate was firstly synthesized using glucosamine hydrochloride as raw materials through cyclization and oxidation. Further, two novel pyrrole ester derivatives were prepared via Steglich esterification from pyrrole intermediate with vanillin and ethyl maltol, respectively. Nuclear magnetic resonance (1 H-NMR, 13 C NMR), infrared spectroscopy (IR) and high resolution mass spectrometry (HRMS) were used to confirm the target compounds. Thermal behavior of the compounds was investigated by thermogravimetry (TG), differential scanning calorimeter (DSC) and the pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) methods. The plausible pyrolytic mechanism was proposed. Additionally, their biological activities against the pathogens Fusarium graminearum, Fusarium oxysporum, Fusarium moniliforme, Phytophthora nicotianae, and Rhizoctonia solani were assessed. These target compounds showed outstanding antifungal activities and the highest inhibitor rates of 62.50 % and 68.75 % against R. solani with EC50 values of 0.0296 and 0.0200 mg mL-1 , respectively. SDHI protein sequence was molecularly docked to identify the binding mechanisms in the active pocket and examine the interactions between both the molecules and the SDHI protein.


Assuntos
Antifúngicos , Fusarium , Antifúngicos/química , Ésteres/farmacologia , Pirróis/farmacologia , Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Relação Estrutura-Atividade
6.
Mikrochim Acta ; 191(6): 328, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743383

RESUMO

The instant screening of patients with a tendency towards developing Alzheimer's disease (AD) is significant for providing preventive measures and treatment. However, the current imaging-based technology cannot meet the requirements in the early stage. Developing biosensor-based liquid biopsy technology could be overcoming this bottleneck problem. Herein, we developed a simple, low-cost, and sensitive electrochemical aptamer biosensor for detecting phosphorylated tau protein threonine 231 (P-tau231), the earliest and one of the most efficacious abnormally elevated biomarkers of AD. Gold nanoparticles (AuNPs) were electrochemically synthesized on a glassy carbon electrode as the transducer, exhibiting excellent conductivity, and were applied to amplify the electrochemical signal. A nucleic acid aptamer was designed as the receptor to capture the P-tau231 protein, specifically through the formation of an aptamer-antigen complex. The proposed biosensor showed excellent sensitivity in detecting P-tau 231, with a broad linear detection range from 10 to 107 pg/mL and a limit of detection (LOD) of 2.31 pg/mL. The recoveries of the biosensor in human serum ranged from 97.59 to 103.26%, demonstrating that the biosensor could be used in complex practical samples. In addition, the results showed that the developed biosensor has good repeatability, reproducibility, and stability, which provides a novel method for the early screening of AD.


Assuntos
Doença de Alzheimer , Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Nanopartículas Metálicas , Proteínas tau , Humanos , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Aptâmeros de Nucleotídeos/química , Proteínas tau/sangue , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Ouro/química , Nanopartículas Metálicas/química , Fosforilação , Biomarcadores/sangue
7.
BMC Med Educ ; 24(1): 662, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877548

RESUMO

BACKGROUND: Good communication is an important professional attribute for radiologists. However, explorations of communication education and their outcomes in radiology residents are sparse. This scoping review aims to evaluate the existing literature on communication education for radiology residents, identify gaps in current practices, and suggest directions for future studies. METHODS: A scoping review following the six-step approach of Arksey and O'Malley was undertaken. We searched through PubMed, Embase, ERIC, and Web of Science databases, focusing on communication education in radiology residents. RESULTS: Sixteen of the 3096 identified articles were included in the analysis. Most studies (13/16) originated from the United States. The studies varied in study design, including quantitative, qualitative and mixed-methods approaches. The sample sizes of most studies were small to moderate, with more than half of the studies had fewer than 30 participants. The identified studies predominantly focused on communication with patients and healthcare professionals. The need for communication education, the efficacy of specific communication education programs, and the capability of some assessment tools for evaluating residents' communication skills were investigated. CONCLUSIONS: This scoping review reveals the gap between the need for communication education and the lack of comprehensive education programs in radiology residents globally. Future studies should develop tailored interventions and use reliable assessment tools, engaging more participants with extended follow-up periods, and expand the scope of communication training to include all relevant stakeholders.


Assuntos
Comunicação , Internato e Residência , Radiologia , Humanos , Radiologia/educação , Competência Clínica , Relações Médico-Paciente , Currículo
8.
Plant Physiol ; 189(3): 1466-1481, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35289870

RESUMO

Red foliated cotton is a typical dominant mutation trait in upland cotton (Gossypium hirsutum). Although mutants have been described, few responsible genes have been identified and characterized. In this study, we performed map-based cloning of the red foliated mutant gene (Re) derived from the cross between G. hirsutum cv. Emian22 and G. barbadense acc. 3-79. Through expression profiling, metabolic pathway analysis, and sequencing of candidate genes, Re was identified as an MYB113 transcription factor. A repeat sequence variation in the promoter region increased the activity of the promoter, which enhanced the expression of Re. Re expression driven by the 35S promoter produced a red foliated phenotype, as expected. When the gene was driven by a fiber elongation-specific promoter, promoter of α-expansin 2 (PGbEXPA2), Re was specifically expressed in 5- to 10-day post-anthesis fibers rather than in other tissues, resulting in brown mature fibers. Re responded to light through phytochrome-interacting factor 4 and formed a dimer with transparent testa 8, which increased its expression as well as that of anthocyanin synthase and UDP-glucose:flavonoid 3-o-glucosyl transferase, and thus activated the entire anthocyanin metabolism pathway. Our research has identified the red foliated mutant gene in cotton, which paves the way for detailed studies of anthocyanin and proanthocyanidin metabolism and pigment accumulation in cotton and provides an alternative strategy for producing brown fiber.


Assuntos
Gossypium , Proantocianidinas , Antocianinas/metabolismo , Fibra de Algodão , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Gossypium/metabolismo , Fenótipo , Proantocianidinas/metabolismo
9.
J Magn Reson Imaging ; 58(5): 1323-1337, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37052571

RESUMO

Cerebral small vessel disease is a major contributor to brain disorders in older adults. It is associated with a much higher risk of stroke and dementia. Due to a lack of clinical and fluid biomarkers, diagnosing and grading small vessel disease are highly dependent on magnetic resonance imaging. In the past, researchers mostly used brain parenchymal imaging markers to represent small vessel damage, but the relationships between these surrogate markers and small vessel pathologies are complex. Recent progress in high-resolution magnetic resonance imaging methods, including time-of-flight MR angiography, phase-contrast MR angiography, black blood vessel wall imaging, susceptibility-weighted imaging, and contrast-enhanced methods, allow for direct visualization of cerebral small vessel structures. They could be powerful tools for understanding aging-related small vessel degeneration and improving disease diagnosis and treatment. This article will review progress in these imaging techniques and their application in aging and disease studies. Some challenges and future directions are also discussed. EVIDENCE LEVEL: 4. TECHNICAL EFFICACY: 3.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Idoso , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Envelhecimento , Angiografia por Ressonância Magnética/métodos
10.
J Magn Reson Imaging ; 57(1): 238-245, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35735742

RESUMO

BACKGROUND: Widespread white matter (WM) injury is a hallmark feature of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). However, controversies about the mechanism of WM tract injury exist persistently. Excessive iron accumulation, frequently reported in CADASIL patients, might cause WM tract injury. PURPOSE: To test the association between iron accumulation and WM tract injury in CADASIL patients. STUDY TYPE: Retrospective. POPULATION: A total of 35 CADASIL patients (age = 50.4 ± 6.4, 62.9% female) and 48 healthy controls (age = 55.7 ± 8.0, 68.8% female). FIELD STRENGTH/SEQUENCE: Diffusion-weighted spin-echo echo-planar sequence; enhanced susceptibility-weighted angiography (ESWAN) gradient echo sequence on a 3 T scanner. ASSESSMENT: The phase images acquired by ESWAN were used to calculate quantitative susceptibility mapping (QSM). Iron accumulation was evaluated in deep gray matters using QSM. WM tract injury was quantified by diffusion metrics based on WM major tracts skeleton. We compared iron deposition between groups and analyzed the correlation between WM tract injury and iron deposition in regions showing significant differences from healthy controls. Exploratory analysis was carried out to investigate whether WM tract injury mediated the relationship between iron deposition and cognitive impairment evaluated by Mini-Mental State Examination (MMSE). STATISTICAL TESTS: General linear model (GLM), partial correlation, stepwise linear regression and mediation analysis were used. The threshold of statistical significance was set as p < 0.05. RESULTS: Compared with healthy controls, CADASIL patients had significantly increased iron deposition in the caudate and putamen. Aberrant iron deposition in these two regions was significantly associated with decreased WM fractional anisotropy (FA) (caudate, r = -0.373; putamen, r = - 0.421), and increased radial diffusivity (RD) (caudate, r = 0.372; putamen, r = 0.386). Furthermore, WM tract injury mediated the relationship between iron deposition and cognitive impairment. DATA CONCLUSION: Patients with CADASIL show increased iron deposition in the caudate and putamen that is correlated to WM tract injury, which may in turn mediate the association with cognitive impairment. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.


Assuntos
CADASIL , Substância Branca , Humanos , Feminino , Masculino , CADASIL/complicações , CADASIL/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Ferro , Encéfalo/diagnóstico por imagem
11.
J Magn Reson Imaging ; 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37737474

RESUMO

BACKGROUND: White matter (WM) degeneration is a key feature of Alzheimer's disease (AD). However, the underlying mechanism remains unclear. PURPOSE: To investigate how amyloid-ß (Aß), tau, and small vascular disease (SVD) jointly affect WM degeneration in subjects along AD continuum. STUDY TYPE: Retrospective. SUBJECTS: 152 non-demented participants (age: 55.8-91.6, male/female: 66/86) from the ADNI database were included, classified into three groups using the A (Aß)/T (tau)/N pathological scheme (Group 1: A-T-; Group 2: A+T-; Group 3: A+T+) based on positron emission tomography data. FIELD STRENGTH/SEQUENCE: 3T; T1-weighted images, T2-weighted fluid-attenuated inversion recovery images, T2*-weighted images, diffusion-weighted spin-echo echo-planar imaging sequence (54 diffusion directions). ASSESSMENT: Free-water diffusion model (generated parameters: free water, FW; tissue fractional anisotropy, FAt; tissue mean diffusivity, MDt); SVD total score; Neuropsychological tests. STATISTICAL TESTS: Linear regression analysis was performed to investigate the independent contribution of AD (Aß and tau) and SVD pathologies to diffusion parameters in each fiber tract, first in the entire population and then in each subgroup. We also investigated associations between diffusion parameters and cognitive functions. The level of statistical significance was set at p < 0.05 (false discovery rate corrected). RESULTS: In the entire population, we found that: 1) Increased FW was significantly associated with SVD and tau, while FAt and MDt were significantly associated with Aß and tau; 2) The spatial pattern of fiber tracts related to a certain pathological marker is consistent with the known distribution of that pathology; 3) Subgroup analysis showed that Group 2 and 3 had more alterations of FAt and MDt associated with Aß and tau; 4) Diffusion imaging indices showed significant associations with cognitive score in all domains except memory. DATA CONCLUSION: WM microstructural injury was associated with both AD and SVD pathologies, showing compartment-specific, tract-specific, and stage-specific WM patterns. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 3.

12.
Eur Radiol ; 33(11): 8057-8066, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37284868

RESUMO

OBJECTIVES: Venous pathology could contribute to the development of parenchymal lesions in cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). We aim to identify presumed periventricular venous infarction (PPVI) in CADASIL and analyze the associations between PPVI, white matter edema, and microstructural integrity within white matter hyperintensities (WMHs) regions. METHODS: We included forty-nine patients with CADASIL from a prospectively enrolled cohort. PPVI was identified according to previously established MRI criteria. White matter edema was evaluated using the free water (FW) index derived from diffusion tensor imaging (DTI), and microstructural integrity was evaluated using FW-corrected DTI parameters. We compared the mean FW values and regional volumes with different levels of FW (ranging from 0.3 to 0.8) in WMHs regions between the PPVI and non-PPVI groups. We used intracranial volume to normalize each volume. We also analyzed the association between FW and microstructural integrity in fiber tracts connected with PPVI. RESULTS: We found 16 PPVIs in 10 of 49 CADASIL patients (20.4%). The PPVI group had larger WMHs volume (0.068 versus 0.046, p = 0.036) and higher FW in WMHs (0.55 versus 0.52, p = 0.032) than the non-PPVI group. Larger areas with high FW content were also found in the PPVI group (threshold: 0.7, 0.47 versus 0.37, p = 0.015; threshold: 0.8, 0.33 versus 0.25, p = 0.003). Furthermore, higher FW correlated with decreased microstructural integrity (p = 0.009) in fiber tracts connected with PPVI. CONCLUSIONS: PPVI was associated with increased FW content and white matter degeneration in CADASIL patients. CLINICAL RELEVANCE STATEMENT: PPVI is an important factor related with WMHs, and therefore, preventing the occurrence of PPVI would be beneficial for patients with CADASIL. KEY POINTS: •Presumed periventricular venous infarction is important and occurs in about 20% of patients with CADASIL. •Presumed periventricular venous infarction was associated with increased free water content in the regions of white matter hyperintensities. •Free water correlated with microstructural degenerations in white matter tracts connected with the presumed periventricular venous infarction.


Assuntos
CADASIL , Substância Branca , Humanos , CADASIL/complicações , CADASIL/diagnóstico por imagem , CADASIL/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Imagem de Tensor de Difusão , Imageamento por Ressonância Magnética/métodos , Edema/patologia , Água , Encéfalo/patologia
13.
Hum Brain Mapp ; 43(17): 5310-5325, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35822593

RESUMO

White matter hyperintensities (WMH) are a typical feature of cerebral small vessel disease (CSVD), which contributes to about 50% of dementias worldwide. Microstructural alterations in deep white matter (DWM) have been widely examined in CSVD. However, little is known about abnormalities in superficial white matter (SWM) and their relevance for processing speed, the main cognitive deficit in CSVD. In 141 CSVD patients, processing speed was assessed using Trail Making Test Part A. White matter abnormalities were assessed by WMH burden (volume on T2-FLAIR) and diffusion MRI measures. SWM imaging measures had a large contribution to processing speed, despite a relatively low SWM WMH burden. Across all imaging measures, SWM free water (FW) had the strongest association with processing speed, followed by SWM mean diffusivity (MD). SWM FW was the only marker to significantly increase between two subgroups with the lowest WMH burdens. When comparing two subgroups with the highest WMH burdens, the involvement of WMH in the SWM was accompanied by significant differences in processing speed and white matter microstructure. Mediation analysis revealed that SWM FW fully mediated the association between WMH volume and processing speed, while no mediation effect of MD or DWM FW was observed. Overall, results suggest that the SWM has an important contribution to processing speed, while SWM FW is a sensitive imaging marker associated with cognition in CSVD. This study extends the current understanding of CSVD-related dysfunction and suggests that the SWM, as an understudied region, can be a potential target for monitoring pathophysiological processes.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Leucoaraiose , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Cognição , Imageamento por Ressonância Magnética
14.
Psychol Med ; 52(5): 834-843, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-32677599

RESUMO

BACKGROUND: Schizotypy refers to schizophrenia-like traits below the clinical threshold in the general population. The pathological development of schizophrenia has been postulated to evolve from the initial coexistence of 'brain disconnection' and 'brain connectivity compensation' to 'brain connectivity decompensation'. METHODS: In this study, we examined the brain connectivity changes associated with schizotypy by combining brain white matter structural connectivity, static and dynamic functional connectivity analysis of diffusion tensor imaging data and resting-state functional magnetic resonance imaging data. A total of 87 participants with a high level of schizotypal traits and 122 control participants completed the experiment. Group differences in whole-brain white matter structural connectivity probability, static mean functional connectivity strength, dynamic functional connectivity variability and stability among 264 brain sub-regions of interests were investigated. RESULTS: We found that individuals with high schizotypy exhibited increased structural connectivity probability within the task control network and within the default mode network; increased variability and decreased stability of functional connectivity within the default mode network and between the auditory network and the subcortical network; and decreased static mean functional connectivity strength mainly associated with the sensorimotor network, the default mode network and the task control network. CONCLUSIONS: These findings highlight the specific changes in brain connectivity associated with schizotypy and indicate that both decompensatory and compensatory changes in structural connectivity within the default mode network and the task control network in the context of whole-brain functional disconnection may be an important neurobiological correlate in individuals with high schizotypy.


Assuntos
Transtorno da Personalidade Esquizotípica , Substância Branca , Encéfalo , Mapeamento Encefálico , Imagem de Tensor de Difusão , Humanos , Imageamento por Ressonância Magnética
15.
Theor Appl Genet ; 135(12): 4483-4494, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36216960

RESUMO

KEY MESSAGE: A fiber length QTL, qFL-c10-1, was fine-mapped to a 96.5-kb region containing one gene that has not been characterized in plants. Fiber length is an important component of cotton fiber quality, which is associated with other quality properties such as fiber strength, fiber maturity, and fineness. In our previous studies, a stable QTL qFL-c10-1 controlling fiber length had been identified on chromosome A10 in an upland cotton recombinant inbred line (RIL) population from a cross between Jimian5 and DH962. To fine-map qFL-c10-1, an F2 population with 1081 individual plants from a cross between a recombinant line DJ61 and Jimian5 was established. Using linkage analysis and progeny recombination experiment, qFL-c10-1 was mapped into a 96.5-kb genomic region that just contained one proper transcript Ghir_A10G022020 (described as GhFL10), an undescribed gene in plants. One 214-bp deletion was identified in the promoter region of DJ61 compared with Jimian5. Quantitative real-time PCR (qRT-PCR) and comparative analysis of parental sequences suggested that GhFL10 was the most promising candidate gene for qFL-c10-1. According to RNA-seq, yeast two-hybrid assay and bimolecular fluorescence complementation (BiFC), we speculate that GhFL10 interacts with NF-YA transcription factors to negatively regulate fiber elongation.


Assuntos
Gossypium , Locos de Características Quantitativas , Gossypium/genética , Mapeamento Cromossômico , Fenótipo , Fibra de Algodão , Estudos de Associação Genética
16.
Plant Biotechnol J ; 19(6): 1170-1182, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33382517

RESUMO

To enrich our knowledge about gene network of fatty acid biosynthesis in cottonseed, we conducted comparative transcriptome to reveal the differences in gene expression between Gossypium hirsutum and Gossypium barbadense during cottonseed development. The prolonged expression period and increased expression abundance of oil-related genes are the main reasons for producing high seed oil content (SOC) in G. barbadense, which manifested as the bias of homeologous gene expression in Dt-subgenome after 25 day postanthesis (DPA). The dynamic expression profile showed that SAD6 and FATA are more important for oil biosynthesis in G. barbadense than that in G. hirsutum. Three key transcription factors, WRI1, NF-YB6 and DPBF2, showed their elite roles in regulating seed oil in cotton. We observed that sequence variations in the promoter region of BCCP2 genes might contribute to its divergence in expression level between the two species. Based on the quantitative trait loci (QTL) information of the seed oil content and utilizing additional G. barbadense introgression lines (ILs), we propose 21 candidate genes on the basis of their differential expression level, of which the GbSWEET and the GbACBP6 showed the potential functional to improve the oil content. Taken together, studying the different expression of oil-related genes and their genetic regulation mechanisms between G. hirsutum and G. barbadense provide new insights to understanding the mechanism of fatty acid biosynthesis network and fatty acid genetic improving breeding in cotton.


Assuntos
Gossypium , Tetraploidia , Redes Reguladoras de Genes , Gossypium/genética , Melhoramento Vegetal , Locos de Características Quantitativas/genética
17.
Psychol Med ; : 1-9, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33775271

RESUMO

BACKGROUND: Anticipatory pleasure deficits are closely correlated with negative symptoms in schizophrenia, and may be found in both clinical and subclinical populations along the psychosis continuum. Prospection, which is an important component of anticipatory pleasure, is impaired in individuals with social anhedonia (SocAnh). In this study, we examined the neural correlates of envisioning positive future events in individuals with SocAnh. METHODS: Forty-nine individuals with SocAnh and 33 matched controls were recruited to undergo functional MRI scanning, during which they were instructed to simulate positive or neutral future episodes according to cue words. Two stages of prospection were distinguished: construction and elaboration. RESULTS: Reduced activation at the caudate and the precuneus when prospecting positive (v. neutral) future events was observed in individuals with SocAnh. Furthermore, compared with controls, increased functional connectivity between the caudate and the inferior occipital gyrus during positive (v. neutral) prospection was found in individuals with SocAnh. Both groups exhibited a similar pattern of brain activation for the construction v. elaboration contrast, regardless of the emotional context. CONCLUSIONS: Our results provide further evidence on the neural mechanism of anticipatory pleasure deficits in subclinical individuals with SocAnh and suggest that altered cortico-striatal circuit may play a role in anticipatory pleasure deficits in these individuals.

18.
J Magn Reson Imaging ; 54(4): 1326-1336, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33998738

RESUMO

BACKGROUND: Perivascular spaces (PVSs) are important component of the brain glymphatic system. While visual rating has been widely used to assess PVS, computational measures may have higher sensitivity for capturing PVS characteristics under disease conditions. PURPOSE: To compute quantitative and morphological PVS features and to assess their associations with vascular risk factors and cerebral small vessel disease (CSVD). STUDY TYPE: Prospective. POPULATION: One hundred sixty-one middle-aged/later middle-aged subjects (age = 60.4 ± 7.3). SEQUENCE: 3D T1-weighted, T2-weighted and T2-FLAIR sequences, and susceptibility-weighted multiecho gradient-echo sequence on a 3 T scanner. ASSESSMENT: Automated PVS segmentation was performed on sub-millimeter T2-weighted images. Quantitative and morphological PVS features were calculated in white matter (WM) and basal ganglia (BG) regions, including volume, count, size, length (Lmaj ), width (Lmin ), and linearity. Visual PVS scores were also acquired for comparison. STATISTICAL TESTS: Simple and multiple linear regression analyses were used to explore the associations among variables. RESULTS: WM-PVS visual score and count were associated with hypertension (ß = 0.161, P < 0.05; ß = 0.193, P < 0.05), as were BG-PVS rating score, volume, count and Lmin (ß = 0.197, P < 0.05; ß = 0.170, P < 0.05; ß = 0.200, P < 0.05; ß = 0.172, P < 0.05). WM-PVS size was associated with diabetes (ß = 0.165, P < 0.05). WM-PVS and BG-PVS were associated with CSVD markers, especially white matter hyperintensities (WMHs) (P < 0.05). Multiple regression analysis showed that WM/BG-PVS quantitative measures were widely associated with vascular risk factors and CSVD markers (P < 0.05). Morphological measures were associated with WMH severity in WM region and also associated with lacunes and microbleeds (P < 0.05) in BG region. DATA CONCLUSION: These novel PVS measures may capture mild PVS alterations driven by different pathologies. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Substância Branca , Idoso , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Substância Branca/diagnóstico por imagem
19.
Hum Brain Mapp ; 41(3): 605-616, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31675160

RESUMO

Cognitive processing speed is crucial for human cognition and declines with aging. White matter hyperintensity (WMH), a common sign of WM vascular damage in the elderly, is closely related to slower psychomotor processing speed. In this study, we investigated the association between WMH and psychomotor speed changes through a comprehensive assessment of brain structural and functional features. Multi-modal MRIs were acquired from 60 elderly adults. Psychomotor processing speeds were assessed using the Trail Making Test Part A (TMT-A). Linear regression analyses were performed to assess the associations between TMT-A and brain features, including WMH volumes in five cerebral regions, diffusivity parameters in the major WM tracts, regional gray matter volume, and brain activities across the whole brain. Hierarchical regression analysis was used to demonstrate the contribution of each index to slower psychomotor processing speed. Linear regression analysis demonstrated that WMH volume in the occipital lobe and fractional anisotropy of the forceps major, an occipital association tract, were associated with TMT-A. Besides, resting-state brain activities in the visual cortex connected to the forceps major were associated with TMT-A. Hierarchical regression showed fractional anisotropy of the forceps major and regional brain activities were significant predictors of TMT-A. The occurrence of WMH, combined with the disruption of passing-through fiber integrity and altered functional activities in areas connected by this fiber, are associated with a decline of psychomotor processing speed. While the causal relationship of this WMH-Tract-Function-Behavior link requires further investigation, this study enhances our understanding of these complex mechanisms.


Assuntos
Envelhecimento/patologia , Envelhecimento/fisiologia , Córtex Cerebral/fisiologia , Leucoaraiose/patologia , Desempenho Psicomotor/fisiologia , Idoso , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Leucoaraiose/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Teste de Sequência Alfanumérica
20.
Stroke ; 50(9): 2568-2570, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31327313

RESUMO

Background and Purpose- We hypothesized the length of delayed-contrast filling sign (DCFS) of intraarterial clot, indicating contrast medium penetration into the thrombus, was associated with stroke etiology. Methods- We retrospectively included patients with large vessel occlusion in anterior circulation who underwent computed tomographic perfusion within 24 hours poststroke onset. We defined DCFS as contrast medium diffusion through the thrombi after the arterial peak phase on 4-dimensional computed tomographic angiography derived from computed tomographic perfusion. We measured the length of DCFS and investigated its value for predicting the stroke etiology. Results- Three hundred twenty-one patients were analyzed, and their stroke etiologies included cardiogenic embolism (CE, n=167), large artery atherosclerosis (n=64), other etiology group (n=4), and undetermined etiology (n=86). CE patients had longer length of DCFS than non-CE patients (2.3 versus 0.5 mm; P<0.001). The optimal cutoff value of DCFS length for predicting CE was 1.5 mm. The sensitivity, specificity, positive predictive value, and negative predictive value of a length of DCFS >1.5 mm for predicting CE were 83.2%, 70.8%, 75.5%, and 79.6%. Conclusions- Longer length of DCFS was associated with CE in patients with large vessel occlusion in anterior circulation, which may provide stroke etiology information.


Assuntos
Aterosclerose/complicações , Embolia/complicações , Tomografia Computadorizada Quadridimensional/efeitos adversos , Acidente Vascular Cerebral/etiologia , Angiografia Cerebral/métodos , Angiografia por Tomografia Computadorizada/métodos , Embolia/diagnóstico , Humanos , Estudos Retrospectivos , Trombose/complicações
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