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1.
Clin Exp Rheumatol ; 42(3): 702-712, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37976115

RESUMEN

OBJECTIVES: Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease. Its diagnosis poses significant challenges especially at early stages and in atypical cases. The aim of this study was to develop a machine learning model based on common laboratory tests that can aid SLE diagnosis. METHODS: A standard protocol was developed to collect data of SLE and control immune diseases. A 10-fold cross-validation was performed in the modeling dataset (n=862), and an external dataset (n=198) was used for model validation. Machine learning algorithms were applied to construct a diagnostic model. Performance was evaluated based on area under the curve (AUC) values, F1-score, negative predictive value, positive predictive value, accuracy, sensitivity, and specificity. RESULTS: The optimal model was based on a random forest algorithm with 10 clinical features. Thrombin time, prothrombin activity, and uric acid contributed most to the diagnostic model. The SLE diagnostic model showed sufficient predictive accuracy, with AUC values of 0.8286 in the validation dataset. CONCLUSIONS: Our diagnostic model based on 10 common laboratory tests identified the patients with SLE with high accuracy. An online version of the model can potentially be applied in clinical settings for the differential diagnosis of SLE.


Asunto(s)
Sistemas de Información en Laboratorio Clínico , Lupus Eritematoso Sistémico , Humanos , Registros Electrónicos de Salud , Lupus Eritematoso Sistémico/diagnóstico , Algoritmos , Aprendizaje Automático
2.
Cereb Cortex ; 33(5): 1972-1984, 2023 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-35580851

RESUMEN

Human performance can be examined using a visual lens. The identification of psychophysical colors and emotional faces with perceptual visual pathways may remain invalid for simple detection tasks. In particular, how the visual dorsal and ventral processing streams handle discriminative visual perceptions and subsequent cognition activities are obscure. We explored these issues using stereoelectroencephalography recordings, which were obtained from patients with pharmacologically resistant epilepsy. Delayed match-to-sample paradigms were used for analyzing the processing of simple colors and complex emotional faces in the human brain. We showed that the angular-cuneus gyrus acts as a pioneer in discriminating the 2 features, and dorsal regions, including the middle frontal gyrus (MFG) and postcentral gyrus, as well as ventral regions, such as the middle temporal gyrus (MTG) and posterior superior temporal sulcus (pSTS), were involved in processing incongruent colors and faces. Critically, the beta and gamma band activities between the cuneus and MTG and between the cuneus and pSTS would tune a separate pathway of incongruency processing. In addition, posterior insular gyrus, fusiform, and MFG were found for attentional modulation of the 2 features via alpha band activities. These findings suggest the neural basis of the discriminative pathways of perception-cognition activities in the human brain.


Asunto(s)
Mapeo Encefálico , Encéfalo , Humanos , Cognición , Percepción Visual , Vías Nerviosas , Imagen por Resonancia Magnética
3.
Memory ; 32(4): 431-448, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38557252

RESUMEN

Remembering life experiences involves recalling not only what occurred (episodic details), but also where an event took place (spatial context), both of which decline with age. Although spatial context can cue episodic detail recollection, it is unknown whether initially recalling an event alongside greater reinstatement of spatial context protects memory for episodic details in the long term, and whether this is affected by age. Here, we analysed 1079 personally-experienced, real-world events from 29 older adults and 12 younger adults. Events were recalled first on average 6 weeks after they occurred and then again on average 24 weeks after they occurred. We developed a novel scoring protocol to quantify spatial contextual details and used the established Autobiographical Interview to quantify episodic details. We found improved recall of episodic details after a delay if those details had initially been recalled situated in greater spatial context. Notably, for both older and younger adults, this preservation was observed for memories initially recalled with low, but not high, numbers of episodic details, suggesting that spatial context aided episodic retrieval for memories that required more support. This work supports the notion that spatial context scaffolds detail-rich event recollection and inspires memory interventions that leverage this spatial scaffold.


Asunto(s)
Memoria Episódica , Recuerdo Mental , Humanos , Masculino , Femenino , Adulto Joven , Anciano , Adulto , Envejecimiento/psicología , Persona de Mediana Edad , Factores de Edad , Señales (Psicología) , Adolescente
4.
Neuroimage ; 277: 120243, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37353098

RESUMEN

Characterizing human thalamocortical network is fundamental for understanding a vast array of human behaviors since the thalamus plays a central role in cortico-subcortical communication. Over the past few decades, advances in functional magnetic resonance imaging have allowed for spatial mapping of intrinsic resting-state functional connectivity (RSFC) between both cortical regions and in cortico-subcortical networks. Despite these advances, identifying the electrophysiological basis of human thalamocortical network architecture remains challenging. By leveraging stereoelectroencephalography electrodes temporarily implanted into distributed cortical regions and the anterior nucleus of the thalamus (ANT) of 10 patients with refractory focal epilepsy, we tested whether ANT stimulation evoked cortical potentials align with RSFC from the stimulation site, derived from a normative functional connectome (n = 1000). Our study identifies spatial convergence of ANT stimulation evoked cortical potentials and normative RSFC. Other than connections to the Papez circuit, the ANT was found to be closely connected to several distinct higher-order association cortices, including the precuneus, angular gyrus, dorsal lateral prefrontal cortex, and anterior insula. Remarkably, we found that the spatial distribution and magnitude of cortical-evoked responses to single-pulse electrical stimulation of the ANT aligned with the spatial pattern and strength of normative RSFC of the stimulation site. The present study provides electrophysiological evidence that stimulation evoked electrical activity flows along intrinsic brain networks connected on a thalamocortical level.


Asunto(s)
Núcleos Talámicos Anteriores , Epilepsias Parciales , Humanos , Corteza Cerebral/fisiología , Lóbulo Parietal , Imagen por Resonancia Magnética , Estimulación Eléctrica , Potenciales Evocados/fisiología
5.
Opt Express ; 31(2): 2508-2522, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36785263

RESUMEN

In this paper, the adaptive liquid (AL) lenses are introduced into the double-sided telecentric zoom system, which could greatly decrease the mechanical motion group compared with the traditional zoom system, and only one movable aperture stop (STO) is retained. Firstly, this paper derived the Gaussian brackets used in this system, and we found the appropriate screening method to get the suitable initial structure parameters from the solution space. Then we used the lens module design method to create the initial system. Finally, we used CODEV to further optimize the system, and we got an excellent design result, which controlled the telecentricity of both sides within 0.1°, the distortion was controlled within 0.5%, and the MTF of each zoom configuration above 0.3. This optical system has high application potential and value in the field of precision machine vision. The design method proposed in this article can effectively solve the problem that the zoom system using adaptive liquid lenses lacks the initial structure.

6.
Opt Express ; 31(22): 36188-36201, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-38017773

RESUMEN

In digital holographic microscopy, aberrations caused by imperfect optical system settings can greatly affect the quantitative measurement of the target phase, so the compensation of aberrations in the distorted phase has become a key point of research in digital holographic microscopy. Here, we propose a fully automatic numerical phase aberration compensation method with fast computational speed and high robustness. The method uses bicubic downsampling to smooth the sample phase for reducing its disturbance to the background aberration fit, while reducing the computational effort of aberration compensation. Polynomial coefficients of the aberration fitting are iteratively optimized in the process of minimizing the global phase gradient by improving the phase gradient operator and constructing the loss function to achieve accurate fitting of the phase aberration. Simulation and experimental results show that the proposed method can achieve high aberration compensation accuracy without prior knowledge of the hologram recording settings or manual selection of the background area free of samples, and it is suitable for samples with moderate and relatively flat background area, which can be widely used in the quantitative analysis of biological tissues and micro and nano structures.

7.
Opt Express ; 31(25): 42015-42035, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38087585

RESUMEN

Composite optical measurement systems are widely used in the field of precision measurement due to their combination of inspection with high accuracy, speed, wide range, real-time, and other advantages. Whereas errors are prevalent in measurements, in order to improve detection accuracy, the systems must be compensated for geometric errors in three-dimensional space. Aiming at the complex situation of multi-probes and multi-zooms in the composite optical measurement system, the current error modelling methods are difficult to be directly applied, so this paper establishes a unified three-dimensional volumetric error model based on the theory of multi-body system and combined with the principle of geometric optics, performs the error verification through the direct measurement method, and finally realises the compensation of geometric error in the continuous space of the whole measurement range. Eventually, the accuracy of the proposed error model and the effectiveness of the error compensation method were verified by a laser interferometer and standard objects to be measured, and the integrated geometric error of the system was decreased by 76.55%, which effectively improved the accuracy of the system. The error modelling and compensation method proposed in this paper provides a new idea for the error compensation of the zoom measurement system, and at the same time, it is universal for the measurement systems of different structures and motion forms, which can be widely used in the field of precision measurement.

8.
Cereb Cortex ; 32(12): 2644-2656, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-34751749

RESUMEN

Dementia causes a substantial global economic burden, but effective treatment is lacking. Recently, studies have revealed that gamma-band waves of electrical brain activity, particularly 40 Hz oscillations, are closely associated with high-order cognitive functions and can activate microglia to clear amyloid-ß deposition. Here, we found that compared with sham stimulation, applying 40-Hz high-frequency repetitive transcranial magnetic stimulation (rTMS) over the bilateral angular gyrus in patients with probable Alzheimer's disease (AD; n = 37) resulted in up to 8 weeks of significantly improved cognitive function. Power spectral density analysis of the resting-state electroencephalography (EEG) demonstrated that 40-Hz rTMS modulated gamma-band oscillations in the left posterior temporoparietal region. Further testing with magnetic resonance imaging and TMS-EEG revealed the following: 40-Hz rTMS 1) prevented gray matter volume loss, 2) enhanced local functional integration within bilateral angular gyrus, as well as global functional integration in bilateral angular gyrus and the left middle frontal gyrus, 3) strengthened information flow from the left posterior temporoparietal region to the frontal areas and strengthened the dynamic connectivity between anterior and posterior brain regions. These findings demonstrate that modulating gamma-band oscillations effectively improves cognitive function in patients with probable AD by promoting local, long-range, and dynamic connectivity within the brain.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedad de Alzheimer/terapia , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/terapia , Electroencefalografía/métodos , Humanos , Estimulación Magnética Transcraneal/métodos
9.
Opt Express ; 30(5): 6981-6990, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35299471

RESUMEN

We present a large-range and high-precision autofocus method based on an annular diffractive optical element (DOE) for a laser direct writing system. By analyzing the shape of the return spot, the defocus direction and the defocus amount can be obtained at the same time. The experimental results show that the linear detection range of the proposed method can reach at least 76 µm, the sensitivity can reach 100 nm, the detection accuracy can reach 100 nm, and the noise fluctuation does not exceed 50 nm. Apparently, with the advantages of a large detection range, high detection, and good stability, the automatic focus detection method proposed in this paper can be widely applied in various wafer-scale complex microstructure preparation systems.

10.
Opt Express ; 30(13): 23511-23530, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-36225029

RESUMEN

We proposed a calibration method for high-precision zoom lenses of optical measurement machines based on Fully Connected Neural Network (FNN), using a 5-layer neural network instead of a camera calibration model, to achieve continuous calibration of zoom lenses at any zoom setting by calibrating typical zooms. From the experimental verification, the average calibration error of this method is 9.83×10-4mm and the average measurement error at any zoom setting is 0.01317mm. The overall calibration precision is better than that of Zhang's calibration method and can meet the application requirements of a high-precision optical measurement machine. The method proposed in this paper provided a new solution and a new idea for the calibration of zoom lenses, which can be widely used in the fields of precision parts inspection and machine-vision measurement.


Asunto(s)
Lentes , Calibración
11.
Exp Cell Res ; 394(1): 112135, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32535035

RESUMEN

Podocytes are actin-rich epithelial cells whose effacement and detachment are the main cause of glomerular disease. Crk family proteins: Crk1/2 and CrkL are reported to be important intracellular signaling proteins that are involved in many biological processes. However, the roles of them in maintaining podocyte morphology and function remain poorly understood. In this study, specific knocking down of Crk1/2 and CrkL in podocytes caused abnormal cell morphology, actin cytoskeleton rearrangement and dysfunction in cell adhesion, spreading, migration, and viability. The p130Cas, focal adhesion kinase, phosphatidylinositol 3-kinase/Akt, p38 and JNK signaling pathways involved in these alterations. Furthermore, knocking down CrkL alone conferred a more modest phenotype than did the Crk1/2 knockdown and the double knockdown. Kidney biopsy specimens from patients with focal segmental glomerulosclerosis and minimal change nephropathy showed downregulation of Crk1/2 and CrkL in glomeruli. In zebrafish embryos, Crk1/2 and CrkL knockdown compromised the morphology and caused abnormal glomerular development. Thus, our results suggest that Crk1/2 and CrkL expression are important in podocytes; loss of either will cause podocyte dysfunction, leading to foot process effacement and podocyte detachment.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Podocitos/metabolismo , Podocitos/patología , Proteínas Proto-Oncogénicas c-crk/metabolismo , Citoesqueleto de Actina/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Glomeruloesclerosis Focal y Segmentaria/genética , Glomeruloesclerosis Focal y Segmentaria/metabolismo , Humanos , Enfermedades Renales/metabolismo , Glomérulos Renales/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo
12.
Psychother Psychosom ; 89(4): 242-250, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32272480

RESUMEN

OBJECTIVE: We explored whether medical health workers had more psychosocial problems than nonmedical health workers during the COVID-19 outbreak. METHODS: An online survey was run from February 19 to March 6, 2020; a total of 2,182 Chinese subjects participated. Mental health variables were assessed via the Insomnia Severity Index (ISI), the Symptom Check List-revised (SCL-90-R), and the Patient Health Questionnaire-4 (PHQ-4), which included a 2-item anxiety scale and a 2-item depression scale (PHQ-2). RESULTS: Compared with nonmedical health workers (n = 1,255), medical health workers (n = 927) had a higher prevalence of insomnia (38.4 vs. 30.5%, p < 0.01), anxiety (13.0 vs. 8.5%, p < 0.01), depression (12.2 vs. 9.5%; p< 0.04), somatization (1.6 vs. 0.4%; p < 0.01), and obsessive-compulsive symptoms (5.3 vs. 2.2%; p < 0.01). They also had higher total scores of ISI, GAD-2, PHQ-2, and SCL-90-R obsessive-compulsive symptoms (p ≤ 0.01). Among medical health workers, having organic disease was an independent factor for insomnia, anxiety, depression, somatization, and obsessive-compulsive symptoms (p < 0.05 or 0.01). Living in rural areas, being female, and being at risk of contact with COVID-19 patients were the most common risk factors for insomnia, anxiety, obsessive-compulsive symptoms, and depression (p < 0.01 or 0.05). Among nonmedical health workers, having organic disease was a risk factor for insomnia, depression, and obsessive-compulsive symptoms (p < 0.01 or 0.05). CONCLUSIONS: During the COVID-19 outbreak, medical health workers had psychosocial problems and risk factors for developing them. They were in need of attention and recovery programs.


Asunto(s)
Ansiedad/etiología , Infecciones por Coronavirus/psicología , Depresión/etiología , Personal de Salud/psicología , Trastorno Obsesivo Compulsivo/etiología , Neumonía Viral/psicología , Trastornos del Inicio y del Mantenimiento del Sueño/etiología , Adolescente , Adulto , Ansiedad/epidemiología , COVID-19 , China/epidemiología , Estudios Transversales , Depresión/epidemiología , Femenino , Humanos , Modelos Logísticos , Masculino , Salud Mental , Persona de Mediana Edad , Análisis Multivariante , Trastorno Obsesivo Compulsivo/epidemiología , Pandemias , Prevalencia , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Encuestas y Cuestionarios , Adulto Joven
13.
J Clin Lab Anal ; 34(8): e23336, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32298022

RESUMEN

BACKGROUND: Chronic kidney disease (CKD) is associated with an increased cardiovascular disease (CVD) mortality risk. Elevation of cardiac biomarkers in patients with renal dysfunction is ambiguous in the diagnosis of CVD. The purpose of this study was to investigate the associations between estimated glomerular filtration rate (eGFR) and cardiac biomarkers, and the influence of renal dysfunction on the cardiac biomarkers. METHODS: We examined the cross-sectional associations of eGFR with cardiac troponin I (cTnI), creatine kinase (CK), CK-MB, lactic dehydrogenase (LDH), hydroxybutyrate dehydrogenase (HBDH), and brain natriuretic peptide (BNP) in 812 adults and 215 child. Spearman correlation and logistic regression analysis were performed to evaluate the associations. RESULTS: For adults, lower eGFR CKD-EPI had significantly higher cTnI, CK-MB, LDH, HBDH, and BNP. There were negative correlations between eGFRCKD-EPI and cTnI, CK-MB, LDH, HBDH, and BNP. After adjustment for potential confounders, as compared with eGFRCKD-EPI  ≥ 90 mL/min/1.73 m2 , eGFRCKD-EPI  < 60 mL/min/1.73 m2 remained associated with a 2.83 (1.08-7.41) [ratio (95% CI)] times higher cTnI and a 6.50 (2.32-18.22) [ratio (95% CI)] times higher HBDH. For child, lower eGFRSchwartz had significant higher CK and CK-MB. There were negative correlations between eGFRSchwartz and CK, and eGFRSchwartz and CK-MB. After adjustment for potential confounders, as compared with eGFRSchwartz  ≥ 90 mL/min/1.73 m2 , eGFRSchwartz  < 90 mL/min/1.73 m2 revealed no significant higher CVD biomarkers. CONCLUSION: Reduced eGFR is associated with elevated cTnI and HBDH among adults without clinically evident CVD, but not child.


Asunto(s)
Creatina Quinasa/sangre , Tasa de Filtración Glomerular/fisiología , Insuficiencia Renal Crónica , Adulto , Anciano , Biomarcadores/sangre , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Hidroxibutirato Deshidrogenasa/sangre , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/fisiopatología , Troponina I/sangre
14.
Acta Neurochir (Wien) ; 162(10): 2499-2507, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32215743

RESUMEN

BACKGROUND: Fear, as one of the basic emotions, is crucial in helping humans to perceive hazards and adapt to social activities. Clinically, fear memory is also involved in a wide spectrum of psychiatric disorders. A better understanding of the neural mechanisms of fear thereby has both neuroscientific and clinical significance. In recent years, data from animal models have demonstrated the key role of the amygdala-hippocampal circuit in the development of fear. However, the neural processing of fear memory remains unclear in humans, which is mainly due to the limitation of indirect measure of neural activity. METHODS: Herein, we investigated fear memory by direct intracranial recordings from 8 intractable epilepsy patients with depth electrodes in both the hippocampus and ipsilateral amygdala. All the patients were subjected to a well-established Pavlovian fear memory paradigm consisted of the familiarization task, conditioning task, and retrieval task, respectively. Simultaneous local field potentials from the hippocampus and amygdala were recorded during different stages. The oscillatory activities from the amygdala and hippocampus were analyzed during fear memory retrieval compared with neutral stages. RESULTS: Consistent with previous rodent studies, our results showed that the amygdala was involved in fear memory retrieval rather than neutral memory retrieval, while the hippocampus was involved both in fear memory retrieval and neutral memory retrieval. In particular, we found that there was an enhanced synchronized activity between the amygdala and hippocampus at beta frequencies (14-30 Hz), which suggested that enhanced synchronized activity at beta frequencies between the amygdala and hippocampus play a pivotal role during retrieval of fear memory in human. CONCLUSIONS: Thus, our observation that the amygdala-hippocampal system contributing to fear memory retrieval in human with frequency-depended specificity has provided new insights into the mechanism of fear and have potential clinical relevance.


Asunto(s)
Amígdala del Cerebelo/fisiología , Ritmo beta , Hipocampo/fisiología , Memoria , Miedo , Humanos
15.
Childs Nerv Syst ; 35(1): 187-190, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30109422

RESUMEN

BACKGROUND: Atlantoaxial dislocation (AAD) is the most common craniovertebral junction malformation (CVJm) which are anomalies of the bones and soft tissues surrounding the foramen magnum. It usually leads to neurologic abnormalities because of instability of this mobile area. But vertebral artery dissection (VAD) caused by AAD is uncommon. CASE REPORT: We report a 15-year-old boy who presented with acute onset of bilateral VAD leading to posterior circulation ischemic stroke (PCIS). Computed tomography angiography (CTA) indicated dissection and occlusion of bilateral intracranial vertebral arteries and AAD with os odontoideum. After antithrombotic treatment for 3 months, the patient got complete revascularization and received posterior C1-C2 fusion. DISCUSSION: There have only been tens of cases of PCIS caused by CVJm. We reviewed these relevant literatures and suggested that more attention should be paid to vascular impairment for patients with CVJm.


Asunto(s)
Articulación Atlantoaxoidea , Luxaciones Articulares/complicaciones , Disección de la Arteria Vertebral/etiología , Adolescente , Angiografía de Substracción Digital , Infarto Cerebral/diagnóstico por imagen , Infarto Cerebral/etiología , Infarto Cerebral/terapia , Revascularización Cerebral , Vértebras Cervicales/cirugía , Fibrinolíticos/uso terapéutico , Humanos , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/terapia , Masculino , Arteria Vertebral/cirugía , Disección de la Arteria Vertebral/diagnóstico por imagen , Disección de la Arteria Vertebral/terapia
16.
Cogn Neurodyn ; 18(3): 893-906, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38826664

RESUMEN

Mental subtraction, involving numerical processing and operation, requires a complex interplay among several brain regions. Diverse studies have utilized scalp electroencephalograph, electrocorticogram, or functional magnetic resonance imaging to resolve the structure pattern and functional activity during subtraction operation. However, a high resolution of the spatial-temporal understanding of the neural mechanisms involved in mental subtraction is unavailable. Thus, this study obtained intracranial stereoelectroencephalography recordings from 20 patients with pharmacologically resistant epilepsy. Specifically, two sample-delayed mismatch paradigms of numeric comparison and subtracting results comparison were used to help reveal the time frame of mental subtraction. The brain sub-regions were chronologically screened using the stereoelectroencephalography recording for mental subtraction. The results indicated that the anterior cortex, containing the frontal, insular, and parahippocampous, worked for preparing for mental subtraction; moreover, the posterior cortex, such as parietal, occipital, limbic, and temporal regions, cooperated during subtraction. Especially, the gamma band activities in core regions within the parietal-cingulate-temporal cortices mediated the critical mental subtraction. Overall, this research is the first to describe the spatiotemporal activities underlying mental subtraction in the human brain. It provides a comprehensive insight into the cognitive control activity underlying mental arithmetic. Supplementary Information: The online version contains supplementary material available at 10.1007/s11571-023-09937-z.

17.
Chin Herb Med ; 15(2): 271-277, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37265763

RESUMEN

Objective: As a medicinal plant, the resource of Rhodiola dumulosa is deficient along with the large collection. For the protection and utilization of R. dumulosa, the influence of plant growth regulators (PGRs) on callus induction and adventitious shoots differentiation, polysaccharide production and the antioxidant activity were tested. Methods: Internodes of R. dumulosa were used as explants and cultured on MS medium plus different plant growth regulators (PGRs). The anti-oxidative activities of polysaccharides were evaluated using radical scavenging assays. Results: By response surface plot, 0.85 mg/L N6-benzyladenine (BA), 0.34 mg/L naphthaleneacetic acid (NAA) and 0.33 mg/L 2,4-dicholorophenoxyacetic acid (2,4-D) were the optimal factors for callus induction (90.03%) from internodes explants on MS medium. The fresh weight of green callus increased 47.26 fold, when callus was inoculated on MS + thidiazuron (TDZ) 0.5 mg/L + NAA 2.0 mg/L. Adventitious buds regenerated from callus on the media of MS were fortified with BA 1.0 mg/L plus NAA 0.5 mg/L, and the induction rate was 40.00%. MS plus indole-3-butyric acid (IBA) 1.0 mg/L produced the highest rooting rate with 10 to 15 roots in a length of 2-3 cm per shoot. The content of total polysaccharides in callus developed on MS + TDZ 0.5 mg/L + NAA 2.0 mg/L and MS + BA 1.0 mg/L + NAA 0.5 mg/L was as high as 1.72%-2.15%. At the dose of 0.5 mg/mL polysaccharides extracted from different callus induced on MS + NAA 2.0 mg/L + TDZ 0.5 mg/L or MS + BA 1.0 mg/L + NAA 0.5 mg/L or MS + BA 0.5 mg/L + 2,4-D 0.5 mg/L, the ABTS radical eliminating percentages were 82.78%, 80.18% and 68.59%, respectively, much higher than that of wild plant. Conclusion: A rapid micropropagation system for R. dumulosa has been developed. The combination of TDZ and NAA or BA and NAA can increase the yield of the total polysaccharides. The polysaccharides isolated from callus and whole wild plants had stronger free radicals scavenging activities, indicating that polysaccharides from R. dumulosa are the potential pharmaceutical supplements.

18.
Plant Physiol Biochem ; 201: 107845, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37364508

RESUMEN

Bryophyllum pinnatum (Lam.) Oken is an ornamental and ethno-medicine plant, which can grow a circle of adventitious bud around the leaf margin. The dynamic change of metabolites during the development of B. pinnatum remains poorly understood. Here, leaves from B. pinnatum at four developmental stages were sampled based on morphological characteristics. A non-targeted metabolomics approach was used to evaluate the changes of endogenous metabolites during adventitious bud formation in B. pinnatum. The results showed that differential metabolites were mainly enriched in sphingolipid metabolism, flavone and flavonol biosynthesis, phenylalanine metabolism, and tricarboxylic acid cycle pathway. The metabolites assigned to amino acids, flavonoids, sphingolipids, and the plant hormone jasmonic acid decreased from period Ⅰ to Ⅱ, and then increased from period Ⅲ to Ⅳ with the emergence of adventitious bud (period Ⅲ). While the metabolites related to the tricarboxylic acid cycle showed a trend of first increasing and then decreasing during the four observation periods. Depending on the metabolite changes, leaves may provide conditions similar to in vitro culture for adventitious bud to occur, thus enabling adventitious bud to grow at the leaf edge. Our results provide a basis for illustrating the regulatory mechanisms of adventitious bud in B. pinnatum.


Asunto(s)
Kalanchoe , Plantas Medicinales , Kalanchoe/química , Extractos Vegetales , Metabolómica , Hojas de la Planta/química
19.
Brain Commun ; 5(2): fcad071, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37056477

RESUMEN

Vertigo is a common neurological complaint, which can result in significant morbidity and decreased quality of life. While pathology to peripheral and subtentorial brain structures is a well-established cause of vertigo, cortical lesions have also been linked to vertigo and may lend insight into relevant neuroanatomy. Here, we investigate the supratentorial lesion locations associated with vertigo and test whether they map to a common brain network. We performed a systematic literature search and identified 23 cases of supratentorial brain lesions associated with vertigo. We mapped the lesion locations to a standard brain template and computed the network of brain regions functionally connected to each lesion location, using a 'wiring diagram' of the human brain termed the human connectome (n = 1000). Sensitivity was assessed by identifying the most common connection to lesion locations associated with vertigo, and specificity was assessed through comparison with control lesions associated with symptoms other than vertigo (n = 68). We found that functional connectivity between lesion locations and the bilateral ventral posterior insula was both sensitive (22/23 lesions) and specific (voxel-wise family-wise error-corrected P < 0.05) for lesion-induced vertigo. We computed connectivity with this hub region to define a lesion-based vertigo network, which included regions in the bilateral insula, somatosensory cortex, higher-level visual areas, cingulate sulcus, thalamus and multiple cerebellar regions in the territory of the posterior inferior cerebellar artery. Next, we used stereo-electroencephalography (80 stimulation sites across 17 patients) to test whether stimulation sites associated with vertigo mapped to this same network. We found that 36/42 (86%) of stimulation sites eliciting vertigo fell within the lesion-based vertigo network in contrast to 16/39 (41%) of stimulation sites that did not elicit vertigo. Connectivity between stimulation sites and our lesion-based hub in the ventral posterior insula was also significantly associated with vertigo (P < 0.0001). We conclude that cortical lesions and direct electrical stimulation sites associated with vertigo map to a common brain network, offering insights into the causal neuroanatomical substrate of vertigo.

20.
Front Hum Neurosci ; 16: 836374, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35601902

RESUMEN

It is a fundamental ability to discriminate incongruent information in daily activity. However, the underlying neural dynamics are still unclear. Using stereoelectroencephalography (SEEG), in this study, we investigated the fine-grained and different states of incongruent information processing in patients with refractory epilepsy who underwent intracranial electrode implantation. All patients performed a delayed match-to-sample paradigm in the sequential pairs of visual stimuli (S1 followed by S2). Participants were asked to discriminate whether the relevant feature of S2 was identical to S1 while ignoring the irrelevant feature. The spatiotemporal cortical responses evoked by different conditions were calculated and compared, respectively, in the context of brain intrinsic functional networks. In total, we obtained SEEG recordings from 241 contacts in gray matter. In the processing of irrelevant incongruent information, the activated brain areas included the superior parietal lobule, supramarginal gyrus, angular gyrus, inferior temporal gyrus, and fusiform gyrus. By comparing the relevant incongruent condition with the congruent condition, the activated brain areas included the middle frontal gyrus, superior temporal gyrus, middle temporal gyrus, posterior superior temporal sulcus, and posterior cingulate cortex. We demonstrated the dynamics of incongruent information processing with high spatiotemporal resolution and suggested that the process of automatic detection of irrelevant incongruent information requires the involvement of local regions and relatively few networks. Meanwhile, controlled discrimination of relevant incongruent information requires the participation of extensive regions and a wide range of nodes in the network. Furthermore, both the frontoparietal control network and default mode network were engaged in the incongruent information processing.

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