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1.
J Biomed Res ; : 1-14, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38807415

RESUMEN

The main pathogenic factor leading to cardiac remodeling and heart failure is myocardial fibrosis. Recent research indicates that microRNAs are essential for the progress of cardiac fibrosis. Myocardial fibrosis is considered to be alleviated through the bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI), which does this by blocking the transforming growth factor ß1 (TGF-ß1) signaling pathway. Here, this study sought to elucidate the post-transcriptional regulation of miR-19a-3p on BAMBI and its role in TGF-ß1-induced cardiac fibroblast activation. Transverse aortic constriction (TAC) caused both myocardial interstitial and perivascular collagen deposition. RT-PCR showed that miR-19a-3p was upregulated in the myocardial tissue of cardiac fibrosis, and TGF-ß1 induced an increase of miR-19a-3p expression in cardiac fibroblasts. The dual-luciferase reporter test and qRT-PCR confirmed that miR-19a-3p directly combined with BAMBI mRNA 3'UTR, thus reduced BAMBI expression, which diminished the capability of BAMBI to inhibit TGF-ß1. Furthermore, miR-19a-3p mimic increased the activation of TGF-ß1/SMAD2/3 pathway signaling, which supported cardiac fibroblast activation, which blocked by overexpression of BAMBI. These findings imply that miR-19a-3p enhances the activation of TGF-ß1/SMAD2/3 by inhibiting BAMBI, further boosting the activation of cardiac fibroblasts, and may thus offer a novel strategy to tackling myocardial fibrosis.

2.
Water Sci Technol ; 86(6): 1342-1357, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36178810

RESUMEN

Microplastic accumulation and resulting degradation are significant threats to the coastal ecosystems around the world. Baseline information on microplastics and their sources is of great importance for a permanent waste management system. The present study focused on the vertical distribution and characteristics of microplastics in the mid-intertidal zone of Donghai Island, China. At eight locations, sediment samples were collected from surface to a depth of 30 cm at intervals of 5 cm. Overall, we found five different polymer types, and vertical distributions of microplastics varied ranging from 0 to 200 particles/kg, with the mean value of 32.92±41.35 particles/kg. Sediment samples collected from all stations contained microplastics with high contribution of fibres. Intruded microplastic materials recorded in sediment samples at a depth of 30 cm demonstrate that microplastics may be present at depths greater than 30 cm. Scanning electron microscopy-energy dispersive X-ray (SEM-EDAX) analysis revealed presence of common elements in the microplastics surface (silicon, aluminium, magnesium, copper, and calcium). Based on the observations and results from this study, we suggest implementing a robust microplastic removal management program in Donghai Island to avoid serious microplastic intrusion effects on benthos and environmental contamination.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Aluminio/análisis , Efectos Antropogénicos , Calcio/análisis , China , Cobre/análisis , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Magnesio/análisis , Plásticos/análisis , Polímeros , Silicio/análisis , Contaminantes Químicos del Agua/análisis
3.
J Pept Sci ; 28(4): e3375, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34725889

RESUMEN

The preparation, self-assembly, and antimicrobial activity of peptides based on TK913 is described. TK9Z4 incorporating a Pro-Pro motif exhibited self-assembly but no cytotoxicity. However, peptide TKZ3 (obtained by changing the amino acid sequence of TK9Z4) showed morphological changes at different concentrations, potent antimicrobial activity, low cytotoxicity, and trypsin resistance. Accordingly, TKZ3 is proposed as new AMP derived from ovalbumin-derived peptides.


Asunto(s)
Péptidos Antimicrobianos , Péptidos , Secuencia de Aminoácidos , Ovalbúmina/química , Péptidos/química
4.
J Hazard Mater ; 404(Pt B): 124143, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33068993

RESUMEN

The hazardous red mud (RM) with high As/F mobility and heavy metal contaminated soil have constituted severe environmental threats. This work demonstrates a "waste to eco-material" strategy through a reliable and low-cost protonation approach to eliminate the As/F leaching risk of RM, and then recycle it as heavy metal passivators for Pb/As polluted soil remediation. The As/F anions have been immobilized by the protonated Fe/Al (hydr)oxides within RM via the formation of stable As/F compounds during the protonation process, which satisfies the requirement by the World Health Organization (As leaching <0.01 mg/L; F leaching <0.8 mg/L). Moreover, in the oilseed rape pot experiments, by adding 30 g/kg stabilized RM into Pb/As polluted soils (100 ~ 300 ppm), benefited from its large adsorption capacity, approximately 40.9 ~ 49.7% Pb and 40.8 ~ 54.8% As concentrations in the plant are reduced without adverse effects. The whole process for RM treatment and soil remediation is cost-effective, straightforward and eco-friendly without secondary pollution or soil degradation. This research provides a green chemical strategy to address both RM recycling and heavy metal contaminated soil remediation problems, which shows high economic feasibility and ecological benefits.

5.
J Pept Sci ; 26(10): e3276, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32715598

RESUMEN

A novel antimicrobial peptide derived from ovalbumin has been discovered. First, the peptide fragment RKIKVYLPRMK (TK9.1) was identified based on computerized predictions of the secondary structure of peptides in a protein data bank. Using HeliQuest, the sequence was developed into RKIKRYLRRMI (TK9.1.3), which was synthesized using Fmoc-solid phase peptide synthesis, and found to have strongly antimicrobial activity against Gram-positive and Gram-negative bacteria, and fungi but not cytotoxic to HeLa cells and hemolysis in mouse red blood cells. Although ovalbumin itself does not have an antibacterial activity, our results suggest that it may supply the organisms that consume it with antimicrobial peptides, in support of their immunodefence.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Ovalbúmina/química , Fragmentos de Péptidos/farmacología , Secuencia de Aminoácidos , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Antifúngicos/síntesis química , Antifúngicos/química , Aspergillus oryzae/efectos de los fármacos , Candida/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Células HeLa , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Micrococcus luteus/efectos de los fármacos , Fragmentos de Péptidos/síntesis química , Fragmentos de Péptidos/química , Estructura Secundaria de Proteína , Pseudomonas/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos
6.
Front Comput Neurosci ; 10: 31, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27148028

RESUMEN

An effective physiological pain assessment method that complements the gold standard of self-report is highly desired in pain clinical research and practice. Recent studies have shown that pain-evoked electroencephalography (EEG) responses could be used as a readout of perceived pain intensity. Existing EEG-based pain assessment is normally achieved by cross-individual prediction (i.e., to train a prediction model from a group of individuals and to apply the model on a new individual), so its performance is seriously hampered by the substantial inter-individual variability in pain-evoked EEG responses. In this study, to reduce the inter-individual variability in pain-evoked EEG and to improve the accuracy of cross-individual pain prediction, we examined the relationship between pain-evoked EEG, spontaneous EEG, and pain perception on a pain EEG dataset, where a large number of laser pulses (>100) with a wide energy range were delivered. Motivated by our finding that an individual's pain-evoked EEG responses is significantly correlated with his/her spontaneous EEG in terms of magnitude, we proposed a normalization method for pain-evoked EEG responses using one's spontaneous EEG to reduce the inter-individual variability. In addition, a nonlinear relationship between the level of pain perception and pain-evoked EEG responses was obtained, which inspired us to further develop a new two-stage pain prediction strategy, a binary classification of low-pain and high-pain trials followed by a continuous prediction for high-pain trials only, both of which used spontaneous-EEG-normalized magnitudes of evoked EEG responses as features. Results show that the proposed normalization strategy can effectively reduce the inter-individual variability in pain-evoked responses, and the two-stage pain prediction method can lead to a higher prediction accuracy.

7.
Front Comput Neurosci ; 10: 32, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27148029

RESUMEN

Pain is a highly subjective experience. Self-report is the gold standard for pain assessment in clinical practice, but it may not be available or reliable in some populations. Neuroimaging data, such as electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), have the potential to be used to provide physiology-based and quantitative nociceptive pain assessment tools that complements self-report. However, existing neuroimaging-based nociceptive pain assessments only rely on the information in pain-evoked brain activities, but neglect the fact that the perceived intensity of pain is also encoded by ongoing brain activities prior to painful stimulation. Here, we proposed to use machine learning algorithms to decode pain intensity from both pre-stimulus ongoing and post-stimulus evoked brain activities. Neural features that were correlated with intensity of laser-evoked nociceptive pain were extracted from high-dimensional pre- and post-stimulus EEG and fMRI activities using partial least-squares regression (PLSR). Further, we used support vector machine (SVM) to predict the intensity of pain from pain-related time-frequency EEG patterns and BOLD-fMRI patterns. Results showed that combining predictive information in pre- and post-stimulus brain activities can achieve significantly better performance in classifying high-pain and low-pain and in predicting the rating of perceived pain than only using post-stimulus brain activities. Therefore, the proposed pain prediction method holds great potential in basic research and clinical applications.

8.
Brain Connect ; 6(6): 496-504, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27105665

RESUMEN

N1 component of auditory evoked potentials is extensively used to investigate the propagation and processing of auditory inputs. However, the substantial interindividual variability of N1 could be a possible confounding factor when comparing different individuals or groups. Therefore, identifying the neuronal mechanism and origin of the interindividual variability of N1 is crucial in basic research and clinical applications. This study is aimed to use simultaneously recorded electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) data to investigate the coupling between N1 and spontaneous functional connectivity (FC). EEG and fMRI data were simultaneously collected from a group of healthy individuals during a pure-tone listening task. Spontaneous FC was estimated from spontaneous blood oxygenation level-dependent (BOLD) signals that were isolated by regressing out task evoked BOLD signals from raw BOLD signals and then was correlated to N1 magnitude across individuals. It was observed that spontaneous FC between bilateral Heschl's gyrus was significantly and positively correlated with N1 magnitude across individuals (Spearman's R = 0.829, p < 0.001). The specificity of this observation was further confirmed by two whole-brain voxelwise analyses (voxel-mirrored homotopic connectivity analysis and seed-based connectivity analysis). These results enriched our understanding of the functional significance of the coupling between event-related brain responses and spontaneous brain connectivity, and hold the potential to increase the applicability of brain responses as a probe to the mechanism underlying pathophysiological conditions.


Asunto(s)
Corteza Auditiva/fisiología , Encéfalo/fisiología , Potenciales Evocados Auditivos , Potenciales Evocados , Estimulación Acústica , Adulto , Percepción Auditiva/fisiología , Mapeo Encefálico , Electroencefalografía , Femenino , Humanos , Individualidad , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/fisiología , Adulto Joven
9.
Hum Brain Mapp ; 37(2): 501-14, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26523484

RESUMEN

Ongoing fluctuations of intrinsic cortical networks determine the dynamic state of the brain, and influence the perception of forthcoming sensory inputs. The functional state of these networks is defined by the amplitude and phase of ongoing oscillations of neuronal populations at different frequencies. The contribution of functionally different cortical networks has yet to be elucidated, and only a clear dependence of sensory perception on prestimulus alpha oscillations has been clearly identified. Here, we combined electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) in a large sample of healthy participants to investigate how ongoing fluctuations in the activity of different cortical networks affect the perception of subsequent nociceptive stimuli. We observed that prestimulus EEG oscillations in the alpha (at bilateral central regions) and gamma (at parietal regions) bands negatively modulated the perception of subsequent stimuli. Combining information about alpha and gamma oscillations predicted subsequent perception significantly more accurately than either measure alone. In a parallel experiment, we found that prestimulus fMRI activity also modulated the perception of subsequent stimuli: perceptual ratings were higher when the BOLD signal was higher in nodes of the sensorimotor network and lower in nodes of the default mode network. Similar to what observed in the EEG data, prediction accuracy was improved when the amplitude of prestimulus BOLD signals in both networks was combined. These findings provide a comprehensive physiological basis to the idea that dynamic changes in brain state determine forthcoming behavioral outcomes. Hum Brain Mapp 37:501-514, 2016. © 2015 Wiley Periodicals, Inc.


Asunto(s)
Ritmo alfa/fisiología , Encéfalo/fisiopatología , Ritmo Gamma/fisiología , Dolor Nociceptivo/fisiopatología , Percepción del Dolor/fisiología , Adolescente , Adulto , Mapeo Encefálico , Circulación Cerebrovascular/fisiología , Electroencefalografía , Femenino , Humanos , Rayos Láser , Imagen por Resonancia Magnética , Masculino , Oxígeno/sangre , Psicofísica , Adulto Joven
10.
J Nanosci Nanotechnol ; 15(7): 5198-201, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26373105

RESUMEN

A Si/Ni/SiOC (SNS) composite structure with high efficiency and long-term cycling stability was synthesized by a cost-effective and scalable method. In this structure, a SiOC net with favorably physical and chemical stability acts as a skeleton to support and segregate Si-Ni mixed powders. The electrochemical performance of Si-Ni as a negative for Li-ion battery had been largely improved through introducing a stable SiOC skeleton structure as buffer base. Compared with Si-Ni mixed powders, the SNS composite negative exhibits excellent long-term cycling stability and capacity. Such SNS composite negative shows excellent cycling stability with a specific capacity of 505.5 mA· h · g(-1) and 84% capacity retention over 25 cycles at 0.2 C rate, which has the perspective application in the future high energy density li-ion batteries. In the meantime, the design and fabrication of this structure has the potential to provide a way for the other functional composite materials in the semiconductive field.

11.
Artículo en Inglés | MEDLINE | ID: mdl-26736832

RESUMEN

Simultaneous collection of electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) data has become increasingly popular in neuroscientific studies, because it can provide neural information with both high spatial and temporal resolution. In order to maximally utilize the information contained in simultaneous EEG-fMRI recording, many sophisticated multimodal data-mining methods, such as joint ICA, have been developed. However, these methods normally deal with data recorded in one experimental condition, and they cannot effectively extract information on activities that are distinct in two conditions. In this paper, a new data decomposition method called joint common spatial pattern (jCSP) is proposed. Compared with previous methods, the jCSP method exploits inter-conditional difference in the strength of brain source activities to achieve source separation, and is able to uncover the source activities with the strongest discriminative power. A group analysis based on clustering is further proposed to reveal distinctive jCSP patterns at group level. We applied joint CSP to a simultaneous EEG-fMRI dataset collected from 21 subjects under two different resting-state conditions (eyes-closed and eyes-open). Results show a distinct dynamic pattern shared by EEG alpha power and fMRI signal during eyes-open resting-state.


Asunto(s)
Encéfalo/fisiología , Electroencefalografía , Imagen por Resonancia Magnética , Algoritmos , Encéfalo/diagnóstico por imagen , Humanos , Oxígeno/sangre , Análisis de Componente Principal , Radiografía , Procesamiento Espacial
12.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 17(3): 171-3, 2005 Mar.
Artículo en Chino | MEDLINE | ID: mdl-15760532

RESUMEN

OBJECTIVE: To observe the effect of combined decompression operation on patients with severe traumatic brain injury complicated by tentorial cerebral herniation. METHODS: Ninety-seven patients with an admission Glasgow Coma Scale score 3-5 were randomly divided into two groups: combined decompression group (n=46), in whom tentorium cerebelli was incised (2-4 cm) combined with bone flap craniectomy decompression [(10-15)cm x (15-17)cm], and conventional temporoparietal craniectomy group (n=51). CT scanning was performed in the patients before and after the operation. The patients of both groups received routine treatment and followed up for 1-32 months (mean 7 months) after the operation. The clinical symptoms, change in intracranial pressure and incidence of complications were compared between the two groups. RESULTS: The efficacious rate was 80.4% (37/46) in the combined decompression group, and among them 27 patients were cured (58.7%) and 10 patients remained to have moderate disability(21.7%). Nine patients (19.6%) died after combined decompression. However, in patients with conventional temporoparietal craniectomy decompression, favorable outcome was only found in 6 cases(11.8%), moderate disability accounted for 21.6% of patients, and 34 patients died(66.6%). In patients with combined decompression, the intracranial pressure was more efficiently lowered compared with conventional craniectomy decompression(P<0.01). Furthermore the incidence of acute brain edema, incisional herniation, traumatic epilepsy, occipital cerebral infarct and cerebro-spinal fluid(CSF) leakage were lower in combined decompression group compared with conventional craniectomy group (P<0.05 or P<0.01). The incidence of intracranial infection was not significantly different between two groups (P>0.05). CONCLUSION: Combined decompression is preferable to routine temporoparietal craniectomy for patients with severe head injury complicated by tentorial herniation.


Asunto(s)
Descompresión Quirúrgica/métodos , Encefalocele/cirugía , Adolescente , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
13.
Artículo en Chino | MEDLINE | ID: mdl-14768084

RESUMEN

OBJECTIVE: To investigate the clinical application of self-cranial bone powder in one stage cranioplasty. METHODS: From October 1999 to December 2002, self-cranial bone powder and medical adhesive were used to repair the skull defect, for one stage cranioplasty, caused by operations on cranium in 128 cases of severe dangerous craniocerebral injury, acute intracranial hematome, sick skull and intracranial tumor. The bone growth was observed by CT or X-ray examination 3-24 months after replantation of cranioplasty. RESULTS: The decompression and cranioplasty were performed simultaneously, the time prolonged 5-10 minutes than that of routine, the appearance of repaired cranial bone was normal, without concavity and convexity. After 12 months of operation, the replanted bone merged with the normal bone completely, with normal appearance. The operation successful rate was 96.1% (123/125) without any complication. Only five cases were not better in growing because of less bone powder, but without cerebral pulse and defective syndrome. All the cases did not need secondary cranioplasty. CONCLUSION: The effect of cranioplasty with self- cranial bone powder effect is good in taking shape. This new method can avoid the traditional secondary cranioplasty for skull defect and complications.


Asunto(s)
Trasplante Óseo/métodos , Traumatismos Craneocerebrales/cirugía , Craneotomía , Cráneo/cirugía , Adolescente , Adulto , Anciano , Regeneración Ósea , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control , Polvos , Procedimientos de Cirugía Plástica , Cráneo/diagnóstico por imagen , Cráneo/lesiones , Adhesivos Tisulares/uso terapéutico , Tomografía Computarizada por Rayos X
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