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1.
Neuroimage ; 293: 120624, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657745

RESUMO

Pain empathy, defined as the ability of one person to understand another person's pain, shows large individual variations. The anterior insula is the core region of the pain empathy network. However, the relationship between white matter (WM) properties of the fiber tracts connecting the anterior insula with other cortical regions and an individual's ability to modulate pain empathy remains largely unclear. In this study, we outline an automatic seed-based fiber streamline (sFS) analysis method and multivariate pattern analysis (MVPA) to predict the levels of pain empathy in healthy women and women with primary dysmenorrhoea (PDM). Using the sFS method, the anterior insula-based fiber tract network was divided into five fiber cluster groups. In healthy women, interindividual differences in pain empathy were predicted only by the WM properties of the five fiber cluster groups, suggesting that interindividual differences in pain empathy may rely on the connectivity of the anterior insula-based fiber tract network. In women with PDM, pain empathy could be predicted by a single cluster group. The mean WM properties along the anterior insular-rostroventral area of the inferior parietal lobule further mediated the effect of pain on empathy in patients with PDM. Our results suggest that chronic periodic pain may lead to maladaptive plastic changes, which could further impair empathy by making women with PDM feel more pain when they see other people experiencing pain. Our study also addresses an important gap in the analysis of the microstructural characteristics of seed-based fiber tract network.


Assuntos
Dismenorreia , Empatia , Individualidade , Córtex Insular , Substância Branca , Humanos , Feminino , Dismenorreia/diagnóstico por imagem , Dismenorreia/fisiopatologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Empatia/fisiologia , Adulto , Adulto Jovem , Córtex Insular/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Dor/psicologia , Dor/fisiopatologia , Dor/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Imageamento por Ressonância Magnética , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Córtex Cerebral/diagnóstico por imagem
2.
Proc Natl Acad Sci U S A ; 118(46)2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34772807

RESUMO

Chronic infection with liver flukes (such as Clonorchis sinensis) can induce severe biliary injuries, which can cause cholangitis, biliary fibrosis, and even cholangiocarcinoma. The release of extracellular vesicles by C. sinensis (CsEVs) is of importance in the long-distance communication between the hosts and worms. However, the biological effects of EVs from liver fluke on biliary injuries and the underlying molecular mechanisms remain poorly characterized. In the present study, we found that CsEVs induced M1-like activation. In addition, the mice that were administrated with CsEVs showed severe biliary injuries associated with remarkable activation of M1-like macrophages. We further characterized the signatures of miRNAs packaged in CsEVs and identified a miRNA Csi-let-7a-5p, which was highly enriched. Further study showed that Csi-let-7a-5p facilitated the activation of M1-like macrophages by targeting Socs1 and Clec7a; however, CsEVs with silencing Csi-let-7a-5p showed a decrease in proinflammatory responses and biliary injuries, which involved in the Socs1- and Clec7a-regulated NF-κB signaling pathway. Our study demonstrates that Csi-let-7a-5p delivered by CsEVs plays a critical role in the activation of M1-like macrophages and contributes to the biliary injuries by targeting the Socs1- and Clec7a-mediated NF-κB signaling pathway, which indicates a mechanism contributing to biliary injuries caused by fluke infection. However, molecules other than Csi-let-7a-5p from CsEVs that may also promote M1-like polarization and exacerbate biliary injuries are not excluded.


Assuntos
Vesículas Extracelulares/metabolismo , Fasciola hepatica/metabolismo , Macrófagos/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Infecção Persistente/parasitologia , Transdução de Sinais/fisiologia
3.
Neuroimage ; 284: 120452, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37949258

RESUMO

Pain empathy is a complex form of psychological inference that enables us to understand how others feel in the context of pain. Since pain empathy may be grounded in our own pain experiences, it exhibits huge inter-individual variability. However, the neural mechanisms behind the individual differences in pain empathy and its association with pain perception are still poorly understood. In this study, we aimed to characterize brain mechanisms associated with individual differences in pain empathy in adult participants (n = 24). The 32-channel electroencephalography (EEG) was recorded at rest and during a pain empathy task, and participants viewed static visual stimuli of the limbs submitted to painful and nonpainful stimulation to solicit empathy. The pain sensitivity of each participant was measured using a series of direct current stimulations. In our results, the N2 of Fz and the LPP of P3 and P4 were affected by painful pictures. We found that both delta and alpha bands in the frontal and parietal cortex were involved in the regulation of pain empathy. For the delta band, a close relationship was found between average power, either in the resting or task state, and individual differences in pain empathy. It suggested that the spectral power in Fz's delta band may reflect subjective pain empathy across individuals. For the alpha band, the functional connectivity between Fz and P3 under painful picture stimulation was correlated to individuals' pain sensitivity. It indicated that the alpha band may reflect individual differences in pain sensitivity and be involved in pain empathy processing. Our results suggested the distinct role of the delta and alpha bands of EEG signals in pain empathy processing and may deepen our understanding of the neural mechanisms underpinning pain empathy.


Assuntos
Empatia , Individualidade , Adulto , Humanos , Eletroencefalografia , Dor , Percepção da Dor/fisiologia
4.
Anal Chem ; 95(2): 594-601, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36541929

RESUMO

In this work, following a metal-ceramic heater (MCH) as an electrothermal vaporizer (ETV), a novel composite Pt/Ni trap based on platinizing the foamed nickel was first fabricated to trap Hg and Cd simultaneously. So, a solid sampling Hg-Cd analyzer was developed to simultaneously detect trace Hg and Cd in soil samples, mainly consisting of an MCH, a composite Pt/Ni trap, and an atomic fluorescence spectrometer (AFS). This small-size MCH-ETV system only consumes 100 W for the complete vaporization of Hg and Cd in soil matrices. The Pt/Ni trap fulfills the complete trapping of Hg and Cd following the solid sampling MCH-ETV system and then fast releases them by heating. It was proved that trapped and released Hg and Cd by the Pt/Ni trap are atomic species using X-ray photoelectron spectroscopy (XPS) and other approaches; specially, the effective cotrapping of Hg and Cd might be due to forming alloys of Hg + Pt and Cd + Ni on the Pt/Ni trap. Under the optimized conditions, the method detection limits (LODs) of Hg and Cd reached 0.4 µg/kg and 0.04 µg/kg for a 20 mg sample size, the relative standard deviations (RSDs) were within 12% and 8% for soil samples, respectively, and the recoveries ranged from 96% to 105%, indicating favorable analytical sensitivity, precision, and accuracy. The whole analysis time can be controlled within 5 min without the soil digestion process. The proposed Hg-Cd analyzer is thus suitable for rapid detection of Hg and Cd in soil samples with advantages such as simplicity, green, and safety. Further, the proposed solid sampling ETV-composite trap method has a promising application potential in the field and rapid detection for multielements.


Assuntos
Cádmio , Mercúrio , Cádmio/análise , Níquel/análise , Mercúrio/análise , Platina/análise , Solo
5.
Hum Brain Mapp ; 44(3): 989-1001, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36269166

RESUMO

Neurovascular (NV) decoupling is a potential neuropathologic mechanism of cognitive impairment in patients with end-stage renal disease (ESRD). Hemodialysis improves cognitive impairment at 24 h post-dialysis, which suggests a potential neuroprotective effect of hemodialysis treatment on the brain. We investigated the effects of hemodialysis treatment on the reversal of NV decoupling associated with cognitive improvement. A total of 39 patients with ESRD and 39 healthy controls were enrolled. All patients were imaged twice during a dialysis session: before hemodialysis (T1pre-dialysis ) and at 24 h after dialysis (T2post-dialysis ). The healthy controls were imaged once. NV coupling was characterized based on correlation coefficients between four types of blood oxygen level-dependent signals and cerebral blood flow (CBF). A battery of neuropsychological and blood tests was performed before the imaging. Patients with ESRD showed improvements in memory and executive function at T2post-dialysis compared with that at T1pre-dialysis . At both T1pre-dialysis and T2post-dialysis , patients with ESRD had lower amplitude of low-frequency fluctuation (ALFF)-CBF coupling than healthy controls. Additionally, patients with ESRD had higher ALFF-CBF coupling at T2post-dialysis than at T1pre-dialysis . Higher memory scores, higher hemoglobin level, lower total plasma homocysteine level, lower systolic blood pressure variance, and lower ultrafiltration volume were associated with higher ALFF-CBF coupling in patients with ESRD after a hemodialysis session. These findings indicate that partial correction of anemia and hyperhomocysteinemia, stable systolic blood pressure, and fluid restriction may be closely linked to the reversal of NV decoupling and improvement in cognition in patients with ESRD.


Assuntos
Disfunção Cognitiva , Falência Renal Crônica , Humanos , Imageamento por Ressonância Magnética/métodos , Diálise Renal , Falência Renal Crônica/complicações , Falência Renal Crônica/diagnóstico por imagem , Falência Renal Crônica/terapia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Encéfalo/diagnóstico por imagem
6.
Hum Brain Mapp ; 44(8): 3084-3093, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36919444

RESUMO

Despite burgeoning evidence for cortical hyperarousal in insomnia disorder, the existing results on electroencephalography spectral features are highly heterogeneous. Phase-amplitude coupling, which refers to the modulation of the low-frequency phase to a high-frequency amplitude, is probably a more sensitive quantitative measure for characterizing abnormal neural oscillations and explaining the therapeutic effect of repetitive transcranial magnetic stimulation in the treatment of patients with insomnia disorder. Sixty insomnia disorder patients were randomly divided into the active and sham treatment groups to receive 4 weeks of repetitive transcranial magnetic stimulation treatment. Behavioral assessments, resting-state electroencephalography recordings, and sleep polysomnography recordings were performed before and after repetitive transcranial magnetic stimulation treatment. Forty good sleeper controls underwent the same assessment. We demonstrated that phase-amplitude coupling values in the frontal and temporal lobes were weaker in Insomnia disorder patients than in those with good sleeper controls at baseline and that phase-amplitude coupling values near the intervention area were significantly enhanced after active repetitive transcranial magnetic stimulation treatment. Furthermore, the enhancement of phase-amplitude coupling values was significantly correlated with the improvement of sleep quality. This study revealed the potential of phase-amplitude coupling in assessing the severity of insomnia disorder and the efficacy of repetitive transcranial magnetic stimulation treatment, providing new insights on the abnormal physiological mechanisms and future treatments for insomnia disorder.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Estimulação Magnética Transcraniana , Humanos , Estimulação Magnética Transcraniana/métodos , Distúrbios do Início e da Manutenção do Sono/terapia , Córtex Pré-Frontal Dorsolateral , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Eletroencefalografia/métodos , Resultado do Tratamento
7.
Acta Radiol ; 64(9): 2636-2645, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37312525

RESUMO

BACKGROUND: Lymphovascular space invasion (LVSI) of endometrial cancer (EC) is a postoperative histological index, which is associated with lymph node metastases. A preoperative acknowledgement of LVSI status might aid in treatment decision-making. PURPOSE: To explore the utility of multiparameter magnetic resonance imaging (MRI) and radiomic features obtained from intratumoral and peritumoral regions for predicting LVSI in endometrioid adenocarcinoma (EEA). MATERIAL AND METHODS: A total of 334 EEA tumors were retrospectively analyzed. Axial T2-weighted (T2W) imaging and apparent diffusion coefficient (ADC) mapping were conducted. Intratumoral and peritumoral regions were manually annotated as the volumes of interest (VOIs). A support vector machine was applied to train the prediction models. Multivariate logistic regression analysis was used to develop a nomogram based on clinical and tumor morphological parameters and the radiomics score (RadScore). The predictive performance of the nomogram was assessed by the area under the receiver operator characteristic curve (AUC) in the training and validation cohorts. RESULTS: Among the features obtained from different imaging modalities (T2W imaging and ADC mapping) and VOIs, the RadScore had the best performance in predicting LVSI classification (AUCtrain = 0.919, and AUCvalidation = 0.902). The nomogram based on age, CA125, maximum anteroposterior tumor diameter on sagittal T2W images, tumor area ratio, and RadScore was established to predict LVSI had AUC values in the training and validation cohorts of 0.962 (sensitivity 94.0%, specificity 86.0%) and 0.965 (sensitivity 90.0%, specificity 85.3%), respectively. CONCLUSION: The intratumoral and peritumoral imaging features were complementary, and the MRI-based radiomics nomogram might serve as a non-invasive biomarker to preoperatively predict LVSI in patients with EEA.


Assuntos
Carcinoma Endometrioide , Nomogramas , Feminino , Humanos , Estudos Retrospectivos , Carcinoma Endometrioide/diagnóstico por imagem , Carcinoma Endometrioide/cirurgia , Imageamento por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética
8.
Sensors (Basel) ; 24(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38202873

RESUMO

The traditional UAV swarm assessment indicator lacks the whole process description of the performance change after the system is attacked. To meet the realistic demand of increasing resilience requirements for UAV swarm systems, in this paper, we study the modeling and resilience assessment methods of UAV swarm self-organized networks. First, based on complex network theory, a double layer coupled UAV swarm network model considering the communication layer and the structure layer is constructed. Then, three network topological indicators, namely, the average node degree, the average clustering factor, and the average network efficiency, are used to characterize the UAV swarm resilience indicators. Finally, the UAV swarm resilience assessment method, considering dynamic evolution, is designed to realize the resilience assessment of the UAV swarm under different strategies in multiple scenarios. The simulation experiments show that the UAV swarm resilience assessment, considering dynamic reconfiguration, has a strong correlation with the network structure design.

9.
Microvasc Res ; 140: 104276, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34742813

RESUMO

PURPOSE: We previously reported that a calpain inhibitor (CAI) prevents the development of atherosclerosis in rats. This study aimed to investigate the effects of CAI (1 mg/kg) on atherosclerosis in apolipoprotein E knockout (ApoE KO) mice that were fed a high-fat diet (HFD) and explore the underlying mechanism by analyzing the expression of genes related to the uptake and efflux of cholesterol. METHODS: Atherosclerotic plaques were evaluated. The activity of calpain in the aorta and that of superoxide dismutase (SOD) in the serum were assessed. Lipid profiles in the serum and liver were examined. Serum oxidized low-density lipoprotein (oxLDL), malondialdehyde (MDA), tumor necrosis factor (TNF-α), and interleukin-6 (IL-6) levels were measured. The mRNA expressions of CD68, TNF-α, IL-6, CD36, scavenger receptor (SR-A), peroxisome proliferator-activated receptor gamma (PPAR-γ), liver-x-receptor alpha (LXR-α), and ATP-binding cassette transporter class A1 (ABCA1) in the aorta and peritoneal macrophages were also evaluated. RESULTS: CAI reduced calpain activity in the aorta. CAI also impeded atherosclerotic lesion formation and mRNA expression of CD68 in the aorta and peritoneal macrophages of ApoE KO mice compared with those of mice receiving HFD. However, CAI had no effect on body weight and lipid levels in both the serum and liver. CAI significantly decreased MDA, oxLDL, TNF-α, and IL-6 levels and increased SOD activity in the serum. Moreover, CAI significantly inhibited the mRNA expression of TNF-α and IL-6 genes in the aorta and peritoneal macrophages. In addition, CAI significantly downregulated the mRNA expression of scavenger receptors CD36 and SR-A and upregulated the expression of genes involved in the cholesterol efflux pathway, i.e., PPAR-γ, LXR-α, and ABCA1 in the aorta and peritoneal macrophages. CONCLUSIONS: CAI inhibited the development of atherosclerotic lesions in ApoE KO mice, and this effect might be related to the reduction of oxidative stress and inflammation and the improvement of cholesterol intake and efflux pathways.


Assuntos
Aorta/efeitos dos fármacos , Doenças da Aorta/prevenção & controle , Aterosclerose/prevenção & controle , Calpaína/antagonistas & inibidores , Colesterol/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Leupeptinas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , RNA Mensageiro/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/metabolismo , Aorta/enzimologia , Aorta/patologia , Doenças da Aorta/enzimologia , Doenças da Aorta/genética , Doenças da Aorta/patologia , Aterosclerose/enzimologia , Aterosclerose/genética , Aterosclerose/patologia , Calpaína/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Metabolismo dos Lipídeos/genética , Receptores X do Fígado/genética , Receptores X do Fígado/metabolismo , Macrófagos Peritoneais/enzimologia , Macrófagos Peritoneais/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , PPAR gama/genética , PPAR gama/metabolismo , Placa Aterosclerótica , RNA Mensageiro/genética , Receptores Depuradores Classe A/genética , Receptores Depuradores Classe A/metabolismo
10.
Anal Chem ; 93(45): 15063-15071, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34706540

RESUMO

In this work, a novel integrated dielectric barrier discharge (IDBD) reactor coupled to an electrothermal vaporizer (ETV) was established for arsenic determination. It is for the first time gas-phase enrichment (GPE) was fulfilled based on the hyphenation of ETV and DBD. The mechanisms of evolution of arsenic atomic and molecular species during vaporization, transportation, trapping, and release processes were investigated via X-ray photoelectron spectroscopy (XPS) and other approaches. Tentative mechanisms were deduced as follows: the newly designed DBD atomizer (DBDA) tube upstream to the air inlet fulfills the atomization of arsenic nanoparticles in vaporized aerosol, leading to free arsenic atoms that are indispensable for forming arsenic oxides; the DBD trap (DBDT) tube traps arsenic oxides under an O2-domininating atmosphere and then releases arsenic atoms under H2-dominating atmospheres. In essence, this process is a physical-chemical process rather than an electrostatic particle deposition. Such a trap and release sequence separates matrix interference and enhances analytical sensitivity. Under the optimized conditions, the method detection limit (LOD) was 0.04 mg/kg and the relative standard deviations (RSDs) were within 6% for As standard solution and real seafood samples, indicating adequate analytical sensitivity and precision. The mean spiked recoveries for laver, kelp, and Undaria pinnatifida samples were 95-110%, and the results of the certified reference materials (CRMs) were consistent with certified values. This ETV-DBD preconcentration scheme is easy and green and has low cost for As analysis in seafood samples. DBD was proved a novel ETV transportation enhancement and preconcentration technique for arsenic, revealing its potential in rapid arsenic analysis based on direct solid sampling ETV instrumentation.


Assuntos
Arsênio , Espectrofotometria Atômica , Volatilização
11.
Hum Brain Mapp ; 42(2): 345-356, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33030796

RESUMO

Primary dysmenorrhea (PDM) is cyclic menstrual pain in the absence of pelvic anomalies, and it is thought to be a sex-hormone related disorder. Existing study has focused on the effects of menstrual cramps on brain function and structure, ignoring the psychological changes associated with menstrual pain. Here we examined whether pain empathy in PDM differs from healthy controls (HC) using task-based functional magnetic resonance imaging (fMRI). Fifty-seven PDM women and 53 matched HC were recruited, and data were collected at the luteal and menstruation phases, respectively. During fMRI scans, participants viewed pictures displaying exposure to painful situations and pictures without any pain cues and assessed the level of pain experienced by the person in the picture. Regarding the main effect of the pain pictures, our results showed that compared to viewing neutral pictures, viewing pain pictures caused significantly higher activation in the anterior insula (AI), anterior cingulate cortex, and the left inferior parietal lobule; and only the right AI exhibited a significant interaction effect (group × picture). Post-hoc analyses confirmed that, relative to neutral pictures, the right AI failed to be activated in PDM women viewing painsss pictures. Additionally, there was no significant interaction effect between the luteal and menstruation phases. It suggests that intermittent pain can lead to abnormal empathy in PDM women, which does not vary with the pain or pain-free phase. Our study may deepen the understanding of the relationship between recurrent spontaneous pain and empathy in a clinical disorder characterized by cyclic episodes of pain.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Dismenorreia/diagnóstico por imagem , Empatia/fisiologia , Ciclo Menstrual/fisiologia , Estimulação Luminosa/métodos , Adulto , Mapeamento Encefálico/métodos , Dismenorreia/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Ciclo Menstrual/psicologia , Medição da Dor/métodos , Medição da Dor/psicologia
12.
Eur Radiol ; 31(5): 3518-3529, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33146792

RESUMO

OBJECTIVES: To evaluate parameters of diffusion-weighted imaging (DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) as early imaging indicators of tumor histologic response to pre-operative neoadjuvant chemotherapy and as probable prognostic factors for event-free survival (EFS) and overall survival in osteosarcoma (OS) in both tumoral and peritumoral areas. METHODS: Thirty-four OS patients who received three courses of neoadjuvant chemotherapy followed by surgery during 2014-2018 were enrolled in this study. All patients underwent baseline and post-chemotherapy DWI and DCE-MRI. Lesion region was defined as the tumoral area and peritumoral area. Parameters of apparent diffusion coefficient, capacity transfer constant (Ktrans), elimination rate constant, extravascular extracellular space volume ratio (Ve), and initial area under the curve as well as corresponding differences between pre- and post-chemotherapy in lesion regions were evaluated. Receiver operating characteristic analysis was used to evaluate the diagnostic performance of these parameters. The associations of all parameters with tumor histologic response, EFS, and overall survival were also calculated. RESULTS: In the tumor area, moderate evidence was found that post-Ktrans was lower in responders as compared with that in poor responders (p = 0.04, false discovery rate [FDR] corrected), and ΔKtrans exhibited significant between-groups differences (p = 0.04, Bonferroni corrected; or p = 0.006, FDR corrected). Weak evidence for the between-groups difference was found in the Ve in the peritumoral area (p = 0.025 before treatment and p = 0.021 after treatment, uncorrected). Furthermore, lower post-Ktrans in the tumoral area and lower pre-Ve in the peritumoral area were significant prognostic indicators for longer EFS (p = 0.002, p = 0.026) and overall survival (p = 0.003, p = 0.023). CONCLUSIONS: In OS, DWI and DCE-MRI parameters in both tumoral and peritumoral areas can reflect the chemotherapy response and prognosticate EFS and overall survival. KEY POINTS: • Peritumoral MRI parameters can reflect the chemotherapy response in OS patients. • Peritumoral MRI parameters can predict EFS and overall survival in OS patients. • MRI parameters may be predictive factors for evaluating chemotherapy efficacy and EFS.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Neoplasias Ósseas/diagnóstico por imagem , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/tratamento farmacológico , Prognóstico
13.
Sheng Li Xue Bao ; 73(3): 407-422, 2021 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-34230943

RESUMO

As the two essential components, the white matter and gray matter compose the central nervous system of the brain. Widely known that axons of neurons mainly form the white matter, and these formed nerve fibers are responsible for transmitting information among various brain regions to achieve the coordinated operation of the entire brain. Early research on the white matter could only be done by dissecting living animals or human cadavers, until Basser et al. proposed diffusion tensor imaging (DTI) technology in 1994, which could detect the diffusion characteristics of water in the brain in vivo noninvasively. Accordingly, this technology could be applied to investigate the diffusion movement of water in white matter to obtain the information of direction and micro-anatomy of white matter fiber bundles. With the advancement on the display and analysis of the anatomical structure of white matter fiber bundles, the exploration of microscopic pathological changes, and the assistance of clinical diagnosis and neurophysiological research, DTI technology has become one of the most popular topics in brain science research. Chronic pain refers to pain lasting more than three months, which not only seriously affects the patient's physical and social functions, but also dramatically reduces the quality of life. It was reported that long-term pain stimulation might cause pathological remodeling of the central nervous system, and abnormalities in white matter were found in imaging examinations of patients with chronic pain. This review introduces the quantitative analysis methods of white matter fiber bundle microstructure based on DTI and its application in chronic pain, and further discusses the application value of DTI technology on clinical research of chronic pain.


Assuntos
Dor Crônica , Substância Branca , Animais , Encéfalo , Dor Crônica/diagnóstico por imagem , Imagem de Tensor de Difusão , Humanos , Qualidade de Vida , Substância Branca/diagnóstico por imagem
14.
Anal Chem ; 92(10): 7257-7264, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32237707

RESUMO

Ultraviolet vapor generation (UVG), as an environmental/user-friendly and efficient sampling approach, was first combined with the gas phase enrichment of Se by dielectric barrier discharge (DBD) microplasma. Volatile Se species from UVG, being much more complicated than conventional hydrides, can be trapped quantitatively (∼100%) on the quartz surface of DBD tube under O2-containing atmosphere and released (∼100%) under H2-containing atmosphere. The absolute detection limit (LOD) for Se was 4 pg (injection volume = 1.2 mL), and the linear (R2 > 0.995) range was 0.05-50 µg/L. The results were in good agreement with those of certified reference materials (CRMs) of water and soil samples, and spiked recoveries for real samples were 90-102% with 1-10% relative standard deviations (RSDs). By gas phase analyte enrichment, the proposed method improved analytical sensitivity (peak height) by 16 times. The mechanism was deduced that dominating SeCO species besides H2Se generating from UVG were all trapped on the DBD quartz tube surface as SeO2 or selenite and then released/transported as atoms to the detection zone. The combination of UVG and DBD can facilitate the green uses, miniaturization, and portability revealing its promising potential in field elemental analysis.

15.
Hum Brain Mapp ; 41(4): 984-993, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31680376

RESUMO

Migraine is a chronic neurological disorder characterized by attacks of moderate or severe headache accompanying functionally and structurally maladaptive changes in brain. As the headache days/month is often measured by patient self-report and tends to be overestimated than actually experienced, the possibility of using neuroimaging data to predict migraine attack frequency is of great interest. To identify neuroimaging features that could objectively evaluate patients' headache days, a total of 179 migraineurs were recruited from two data center with one dataset used as the training/test cohort and the other used as the validating cohort. The guidelines for controlled trials of prophylactic treatment of chronic migraine in adults were used to identify the frequency of attacks and migraineurs were divided into low (MOl) and high (MOh) subgroups. Whole-brain functional connectivity was used to build multivariate logistic regression models with model iteration optimization to identify MOl and MOh. The best model accurately discriminated MOh from MOl with AUC of 0.91 (95%CI [0.86, 0.95]) in the training/test cohort and 0.79 in the validating cohort. The discriminative features were mainly located within the limbic lobe, frontal lobe, and temporal lobe. Permutation tests analysis demonstrated that the classification performance of these features was significantly better than chance. Furthermore, the indicator of functional connectivity had a higher odds ratio than behavioral variables with implementing a holistic regression analysis. The current findings suggested that the migraine attack frequency could be distinguished by using machine-learning algorithms, and highlighted the role of brain functional connectivity in revealing underlying migraine-related neurobiology.


Assuntos
Conectoma/métodos , Lobo Frontal/fisiopatologia , Lobo Límbico/fisiopatologia , Transtornos de Enxaqueca/diagnóstico por imagem , Transtornos de Enxaqueca/fisiopatologia , Rede Nervosa/fisiopatologia , Lobo Temporal/fisiopatologia , Adulto , Feminino , Lobo Frontal/diagnóstico por imagem , Humanos , Lobo Límbico/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Prognóstico , Lobo Temporal/diagnóstico por imagem
16.
Neuroradiology ; 62(3): 369-375, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31792569

RESUMO

PURPOSE: Refractory hemifacial contraction and comorbid emotional disorders are major annoyance suffered by patients with hemifacial spasm (HFS). It is currently unknown how whiter matter (WM) abnormalities in the brain contribute to HFS. METHODS: To investigate WM alterations in HFS, 26 patients and 29 matched healthy controls were ultimately recruited in this experiment. The whole brain diffusion tensor imaging (DTI) was acquired at 3.0 Tesla scanner. Tract-based spatial statistics (TBSS) analysis was applied to investigate the differences of DTI metrics (fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) axial diffusivity (AD)) between HFS patients and controls throughout brain WM. The relationship between the severity of facial spasm and affective disturbance in HFS patients, and WM abnormalities was examined using spearman correlation analyses. RESULTS: TBSS method showed structural alterations in the genu and body of corpus callosum; bilateral inferior longitudinal fasciculus (ILF) and inferior frontal-occipital fasciculus (IFOF); left superior longitudinal fasciculus, anterior, posterior, and superior portion of corona radiata; left posterior limb of the internal capsule; and left posterior thalamic radiation in HFS patients compared with healthy subjects. In addition, the overlapped region of decreased FA together with increased RD and MD was merely localized in the right ILF and IFOF in the HFS group, and abnormality of RD value in this region was positively correlated with the patients' spasm score. CONCLUSIONS: The present study indicate extensive disruptions of WM integrity, especially the RD changes in right ILF and IFOF, which may provide alternative imaging clues for evaluating the characteristics of HFS.


Assuntos
Imagem de Tensor de Difusão/métodos , Espasmo Hemifacial , Substância Branca/diagnóstico por imagem , Anisotropia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
17.
Hum Brain Mapp ; 40(1): 284-292, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30256491

RESUMO

To investigate whether interindividual variability of white matter (WM) tract microstructure of the medial prefrontal cortex (mPFC)-amygdala circuit could predict 8-week placebo treatment outcomes in patients with migraine without aura (MO) using diffusion tensor imaging (DTI) with a tractography atlas-based analysis algorithm and a linear support vector machine algorithm. This study received institutional review board approval, and all subjects gave informed consent. One hundred and twenty-four MO had an 8-week sham acupuncture treatment. Patients were subdivided into recovering (MOr, >50% improvement in migraine attack frequency after treatment) and persisting (MOp, <50% reduction in number of migraine days). Neuroimaging was collected via magnetic resonance imaging (MRI) in all subjects. Patients were imaged during the interictal phase of migraine (at least 72 hr after, and not within 24 hr of a migraine) before the treatment. WM microstructures were quantified along the selected fiber pathway and were used to evaluate the discrimination performance for classifying MOr and MOp. The combined features of diffusion measures from vertices along the pathways of the mPFC-amygdala accurately discriminated MOr from MOp migraineurs with an accuracy of 84.0% (p < .005, permutation test). The most discriminative WM features that contributed to the classification were located in the external capsule and ACC/mPFC. Our findings suggested that the variability of placebo treatment outcomes in migraineurs could be predicted from priori diffusion measures along the fiber pathways of the mPFC-amygdala, which may demonstrate a potential of WM neuroimaging features as imaging markers for identifying placebo responders in migraine patients.


Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Enxaqueca sem Aura/diagnóstico por imagem , Enxaqueca sem Aura/terapia , Avaliação de Resultados em Cuidados de Saúde , Efeito Placebo , Córtex Pré-Frontal/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Terapia por Acupuntura , Adulto , Tonsila do Cerebelo/patologia , Biomarcadores , Imagem de Tensor de Difusão , Humanos , Individualidade , Enxaqueca sem Aura/patologia , Placebos , Córtex Pré-Frontal/patologia , Substância Branca/patologia , Adulto Jovem
18.
Anal Chem ; 90(10): 6332-6338, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29688699

RESUMO

The mechanisms of arsenic gas phase enrichment (GPE) by dielectric barrier discharge (DBD) was investigated via X-ray photoelectron spectroscopy (XPS), in situ fiber optic spectrometer (FOS), etc. It proved for the first time that the arsenic species during DBD trapping, release, and transportation to the atomic fluorescence spectrometer (AFS) are probably oxides, free atoms, and atom clusters, respectively. Accordingly, a novel in situ DBD trap as a GPE approach was redesigned using three-concentric quartz tube design and a modified gas line system. After trapping by O2 at 9.2 kV, sweeping for 180 s, and releasing by H2 at 9.5 kV, 2.8 pg detection limit (LOD) was achieved without extra preconcentration (sampling volume = 2 mL) as well as 4-fold enhancement in absolute sensitivity and ∼10 s sampling time. The linearity reached R2 > 0.998 in the 0.1-8 µg/L range. The mean spiked recoveries for tap, river, lake, and seawater samples were 100-106%; and the measurements of the certified reference materials (CRMs) were in good agreement with the certified values. In situ DBD trap is also suitable to atomic absorption spectrometry (AAS) or optical emission spectrometry (OES) for fast and on-site determination of multielements.


Assuntos
Arsênio/análise , Espectrofotometria Atômica/instrumentação , Espectrofotometria Atômica/métodos
19.
Hum Brain Mapp ; 39(12): 4766-4775, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30062855

RESUMO

The brain-kidney crosstalk theory suggested that the brain and kidneys may be considered end organs on parallel trajectories and subject to shared risk factors, which are receiving increasing attention. Cognitive control deficits were frequently presented in patients with end-stage renal disease (ESRD). Whether or not cognitive control impairment is concerned with brain-kidney crosstalk is in need of further research. To detect the relationship between ESRD and cognitive control impairment, diffusion tensor imaging was collected in 64 healthy controls (HCs) and 64 patients with ESRD. Tract-based spatial statistics and fixel-based analysis were used to detect the difference of white matter (WM) microstructure and morphology between ESRD patients and HCs in the whole brain. Tractography atlas-based analysis was also used to investigate the difference of diffusional characteristics along fiber bundles of interest between the two groups. For the whole-brain analysis, ESRD patients showed WM microstructural alteration and fiber density variation in the cingulum. In addition, ESRD patients exhibited higher MD and RD than HCs along the anterior cingulum. Among all of the blood biochemistry tests that represent kidney disease to a degree, the stepwise regression analysis showed that only hemoglobin significantly contributed to the cognitive control deficits in ESRD patients. Mediation analysis proved that the relationship between hemoglobin and cognitive control deficits of ESRD patients was mediated by WM microstructural alteration of the cingulum. Our results indicated that the anterior cingulum was correlated with cognitive control deficits and mediated the impact of hemoglobin on cognitive control.


Assuntos
Disfunção Cognitiva , Imagem de Tensor de Difusão/métodos , Função Executiva/fisiologia , Giro do Cíngulo/patologia , Hemoglobinas , Falência Renal Crônica/sangue , Falência Renal Crônica/complicações , Substância Branca/patologia , Adulto , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Masculino , Substância Branca/diagnóstico por imagem
20.
Neurol Sci ; 39(1): 119-125, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29063453

RESUMO

Numerous studies have indicated an association between migraine and right-to-left shunt. However, little is known about whether right-to-left shunt has an effect on the migraine brain. This observational study aims to explore the impact of right-to-left shunt on the brain of migraine without aura on microstructural level. Thirty-five patients with migraine without aura were enrolled in this study. Contrast-enhanced Transcranial Doppler was performed to evaluate the status of right-to-left shunt. Three-dimensional T1-weighted and diffusion tensor images were acquired for data analysis. We employed voxel-based morphometry and tract-based spatial statistical analyses to assess the differences of gray and white matter between migraineurs with and without right-to-left shunt, respectively. Among the 35 patients, 19 (54.3%) patients had right-to-left shunt. There were no significant differences in headache features between migraineurs with and without right-to-left shunt. There were significant increases of mean and radial diffusivity in migraineurs with right-to-left shunt compared with migraineurs without right-to-left shunt. The alterations were primarily located in the right posterior thalamic radiation, secondly in the body of corpus callosum and the right superior corona radiata. No significant differences were observed in values of fractional anisotropy and axial diffusivity. No significant between-group differences were found in gray matter volume. Right-to-left shunt may cause alterations of white matter integrity in migraine without aura, and the alterations are more likely to be located at the posterior circulation.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/patologia , Defeitos dos Septos Cardíacos/complicações , Enxaqueca sem Aura/patologia , Substância Branca/patologia , Adulto , Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão , Feminino , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Enxaqueca sem Aura/complicações , Enxaqueca sem Aura/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana
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