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1.
Small ; 19(23): e2206091, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36855335

RESUMO

Bulk nanobubbles fascinate scientists because of their stability over long periods of time and their ability to carry gases, leading to numerous potential applications. Considering the hypoxic tumor microenvironment and the advantages of bulk nanobubbles, lipid-encapsulated oxygen nanobubbles are prepared from free bulk oxygen nanobubbles in this study. The obtained carrier is then modified with a protein fused with the single-chain antibody of human epidermal growth factor receptor 2 (anti-HER2 scFv) and tandem-repeat cytochrome c (anti-HER2 scFv-nCytc) to enhance tumor targeting and induce tumor apoptosis. Copper phthalocyanine is used as the photosensitizer to demonstrate how the oxygen in the nanobubbles affects the efficiency of photodynamic therapy (PDT). The combination of anti-HER2 scFv-nCytc and PDT synergistically improves the therapeutic effect and alleviates hypoxia in tumors in vivo while causing little inflammatory response. Based on the findings, bulk nanobubble water shows promise in the targeted delivery of oxygen and can be combined with antibody therapy to enhance the efficiency of PDT.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Oxigênio/farmacologia , Hipóxia , Apoptose , Lipídeos , Linhagem Celular Tumoral , Microambiente Tumoral
2.
Crit Rev Food Sci Nutr ; 63(21): 5414-5429, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34961384

RESUMO

Deep-fried meat products are widely popular. However, harmful compounds produced by various chemical reactions during frying have been shown to be detrimental to human health. It is of great necessity to raise practical suggestions for improving the oxidation problem of frying oils and frying conditions in some aspects. Vegetable oils are not as thermally stable as saturated fats, and blended oils have higher thermal stability than single oil. In this review, we discussed the oxidation problems frying oils and meats are subject to during frying, starting from the oil oxidation mechanism, the effects of different oils and fats on the quality of different fried meats under different conditions were concluded to alleviate the oxidation problem, to highlight the necessity of applying blended oils for frying, and effective antioxidants added to frying oils are also introduced, that would provide more convenient and practical options for obtaining higher quality of fried meat products and offer better understanding of the potential of blended frying oils for frying meat products.


Assuntos
Antioxidantes , Temperatura Alta , Humanos , Antioxidantes/análise , Óleos de Plantas/química , Ácidos Graxos/análise , Carne/análise , Culinária
3.
Crit Rev Food Sci Nutr ; 63(24): 6738-6756, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35174744

RESUMO

Carbon dots (CDs) have two unique advantages: one is ease of synthesis at low price, the other is desirable physical and chemical properties, such as ultra-small size, abundant surface functional groups, nontoxic/low-toxicity, good biocompatibility, excellent antibacterial and antioxidant activities etc. These advantages provide opportunities for the development of new food packaging enhancers and food preservatives. This paper systematically reviews the studies of CDs used to strengthen the physical properties of food packaging, including strengthen mechanical strength, ultraviolet (UV) barrier properties and water barrier properties. It also reviews the researches of CDs used to fabricate active packaging with antioxidant and/or antibacterial properties and intelligent packaging with the capacity of sensing the freshness of food. In addition, it analyzes the antioxidant and antibacterial properties of CDs as preservatives, and discusses the effect of CDs applied as coating agents and nano-level food additives for extension the shelf life of food samples. It also provides a brief review on the security and the release behavior of CDs.


Collect and analyze the effect of CDs on enhancing the physical properties of protective food packaging.Discuss the active of CDs and their application in active intelligent packaging.Analyze the application of CDs as coating agent and nano-level food additives.Discuss the security of CDs, including toxicity and the release behavior.


Assuntos
Antioxidantes , Conservantes de Alimentos , Conservantes de Alimentos/farmacologia , Conservantes de Alimentos/química , Antioxidantes/farmacologia , Carbono/química , Conservação de Alimentos , Embalagem de Alimentos , Antibacterianos
4.
Brain ; 145(5): 1653-1667, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35416942

RESUMO

Epilepsy presurgical investigation may include focal intracortical single-pulse electrical stimulations with depth electrodes, which induce cortico-cortical evoked potentials at distant sites because of white matter connectivity. Cortico-cortical evoked potentials provide a unique window on functional brain networks because they contain sufficient information to infer dynamical properties of large-scale brain connectivity, such as preferred directionality and propagation latencies. Here, we developed a biologically informed modelling approach to estimate the neural physiological parameters of brain functional networks from the cortico-cortical evoked potentials recorded in a large multicentric database. Specifically, we considered each cortico-cortical evoked potential as the output of a transient stimulus entering the stimulated region, which directly propagated to the recording region. Both regions were modelled as coupled neural mass models, the parameters of which were estimated from the first cortico-cortical evoked potential component, occurring before 80 ms, using dynamic causal modelling and Bayesian model inversion. This methodology was applied to the data of 780 patients with epilepsy from the F-TRACT database, providing a total of 34 354 bipolar stimulations and 774 445 cortico-cortical evoked potentials. The cortical mapping of the local excitatory and inhibitory synaptic time constants and of the axonal conduction delays between cortical regions was obtained at the population level using anatomy-based averaging procedures, based on the Lausanne2008 and the HCP-MMP1 parcellation schemes, containing 130 and 360 parcels, respectively. To rule out brain maturation effects, a separate analysis was performed for older (>15 years) and younger patients (<15 years). In the group of older subjects, we found that the cortico-cortical axonal conduction delays between parcels were globally short (median = 10.2 ms) and only 16% were larger than 20 ms. This was associated to a median velocity of 3.9 m/s. Although a general lengthening of these delays with the distance between the stimulating and recording contacts was observed across the cortex, some regions were less affected by this rule, such as the insula for which almost all efferent and afferent connections were faster than 10 ms. Synaptic time constants were found to be shorter in the sensorimotor, medial occipital and latero-temporal regions, than in other cortical areas. Finally, we found that axonal conduction delays were significantly larger in the group of subjects younger than 15 years, which corroborates that brain maturation increases the speed of brain dynamics. To our knowledge, this study is the first to provide a local estimation of axonal conduction delays and synaptic time constants across the whole human cortex in vivo, based on intracerebral electrophysiological recordings.


Assuntos
Epilepsia , Potenciais Evocados , Teorema de Bayes , Encéfalo , Mapeamento Encefálico/métodos , Estimulação Elétrica/métodos , Potenciais Evocados/fisiologia , Humanos
5.
Environ Res ; 238(Pt 2): 117247, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37769833

RESUMO

Freshwater lakes undergo substantial alterations of the phosphorus (P) cycle in the water-sediment ecosystem due to thermal change. The impact process of seasonal fluctuation on P cycling in sediments has been scarcely investigated. P forms in sediments from a freshwater lake in China were analyzed using sequential extraction technique. The vertical distribution of soluble reactive P (SRP), Fe2+, and S2- in the interstitial water was measured using diffusion gradient technique (DGT). Fick's Law and DIFS model were used to obtain the diffusion fluxes of SRP and the kinetic parameters in the water-sediment system. The results showed that total P (TP) concentrations in the solid sediments varied from 207.5, 266.6 and 130.3 mg/kg to 614.7, 1053.1, and 687.6 mg/kg in winter, spring, and summer, respectively. The concentrations of individual P forms in spring were higher than those in other seasons, with Fe-bound P (Fe-P) concentration being the highest across all seasons. Notably, significant variations of SRP concentrations were found in the interstitial water between sedimentary depths of approximately 2 cm and 6 cm, particularly in the summer. Furthermore, higher diffusion fluxes of SRP through the interface were found in summer. A stable anaerobic environment failed to develop in spring with high water level, preventing the desorption of solid Fe-P and diffusion of Fe2+ into the water due to the afflux and deposition of P-containing particulate into deeper sediment layers along with organic material. Under extreme high-temperature in summer, decreased rainfall and rising temperatures boosted the activity of aquatic organisms in the water, thereby reducing P fixation by sediments and leading to P release. This process increased the risk of P excess and potential eutrophication in the water. Generally, clarifying the resupplying processes of endogenous P in sediment systems experiencing seasonal variations is critical for eutrophication management of lakes.


Assuntos
Lagos , Poluentes Químicos da Água , Estações do Ano , Água , Fósforo/análise , Ecossistema , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Monitoramento Ambiental/métodos , Eutrofização , China
6.
J Environ Manage ; 341: 118050, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37141713

RESUMO

Nitrogen (N) reduction processes including denitrification and dissimilatory nitrate reduction to ammonium (DNRA) are critical for the eutrophication in the lake water. However, the understanding about the dominant pathways of N cycling keep limited due to the high complexity of N cycle processes in lacustrine environment. The N fractions in sediments collected from Shijiuhu Lake were measured using high-resolution (HR)-Peeper technique and chemical extraction method in varied seasons. The abundance and microbial community compositions of functional genes involved in various N-cycling processes were also obtained using high-throughput sequencing. The results showed that NH4+ concentrations in the pore water remarkably increased from the upper layer toward the deeper layer and from winter to spring. This trend suggested that higher temperature facilitated the accumulation of NH4+ in the water. Decreased NO3- concentrations were also detected at deeper sediment layers and higher temperature, indicating the intensification of N reduction on anaerobic conditions. The NH4+-N concentrations reduced in spring along with the slight change of NO3--N in solid sediment, indicating the desorption and release of mobile NH4+ from solid phase to the solution. Remarkably decreased absolute abundances of functional genes were found in spring with DNRA bacteria nrfA gene as dominant genus and Anaeromyxobacter as the most dominant bacterium (21.67 ± 1.03%). Higher absolute abundance (146.2-788.1 × 105 Copies/g) of nrfA gene relative to other genes was mainly responsible for the increase of bio-available NH4+ in the sediments. Generally, microbial DNRA pathway predominated the N reduction and retention processes in the lake sediment at higher temperature and water depth even experiencing the suppression of DNRA bacteria abundance. These results suggested the existence of ecological risk via N retention by the action of the DNRA bacteria in the sediment on the condition of higher temperature, further provided valuable information for N management of eutrophic lakes.


Assuntos
Compostos de Amônio , Nitratos , Poluentes Químicos da Água , Compostos de Amônio/metabolismo , Bactérias/genética , Bactérias/metabolismo , Desnitrificação , Lagos/química , Nitratos/análise , Nitrogênio , Compostos Orgânicos , Oxirredução , Estações do Ano , Água
7.
J Environ Manage ; 340: 118016, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37121007

RESUMO

Identifying phosphorus (P) sources and contributions from terrestrial sources is important for clean water and eutrophication management in lake watersheds. However, this remains challenging owing to the high complexity of P transport processes. The concentrations of different P fractions in the soils and sediments from Taihu Lake, a representative freshwater lake watershed, were obtained using sequential extraction procedure. The dissolved phosphate (PO4-P) and alkaline phosphatase activity (APA) in the lake's water were also surveyed. The results showed that different P pools in the soil and sediments displayed different ranges. Higher concentrations of P fractions were measured in the solid soils and sediments from the northern and western regions of the lake watershed, indicating a larger input of P from exogenous sources, including agriculture runoff and industrial effluent from the river. Generally, higher Fe-P and Ca-P concentrations of up to 399.5 and 481.4 mg/kg were detected in soils and lake sediments, respectively. Similarly, the lake's water had higher concentrations of PO4-P and APA in the northern region. A significant positive correlation was found between Fe-P in the soil and PO4-P concentrations in the water. Statistical analysis indicated that appropriately 68.75% P was retained in the sediment from terrigenous sources, and 31.25% P experienced dissolution and shifted to the solution phase in the water-sediment ecosystems. The dissolution and release in Fe-P in the soils were responsible for the increase of Ca-P in the sediment after the afflux of soils into the lake. These findings suggest that soil runoff predominantly controls P occurrence in lake sediments as an exogenous source. Generally, the strategy of reducing terrestrial inputs from agricultural soil discharge is still an important step in P management at the catchment scale of lakes.


Assuntos
Lagos , Poluentes Químicos da Água , Fósforo/análise , Ecossistema , Sedimentos Geológicos , Monitoramento Ambiental/métodos , Solo , Água/análise , China , Poluentes Químicos da Água/análise , Eutrofização
8.
Crit Rev Food Sci Nutr ; : 1-22, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35766478

RESUMO

With the increase of people's awareness of food safety, it is crucial to find natural and green antimicrobial agents to replace traditional antimicrobial agents. Essential oils of spices (SEOs) are low toxicity or nontoxic, which exhibited antioxidants and antimicrobial activity according to many in vitro and in situ experiments. Spices are widely available and low cost as a plant raw material for the extraction of SEOs. This review summarized highly efficient extraction techniques for SEOs, such as physical field assisted extraction technology, supercritical fluid extraction, and biological-based techniques. Furthermore, purification of SEOs and components were also recapitulated. Purification techniques of SEOs improve their utilization value due to the increased content of bioactive components. Finally, the review concentrated on the applications of SEOs in food industry, including food preservation, food active packaging by means of films or coatings, antioxidant properties. In addition, addressing the problem of unstability of SEOs and its role to inhibit the pathogenic bacteria, the encapsulation of SEOs for use in the food industrial sectors reduces the safety risk to human health.

9.
Crit Rev Food Sci Nutr ; : 1-15, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36300891

RESUMO

Prepared dishes are increasingly popular convenience food that can be eaten directly from hygienic packaging by heating. Physics field (PF) is food processing method built with physical processing technology, which has the characteristics of high efficiency and environmental safety. This review focuses on summarizing the application of PFs in prepared dishes, evaluating and comparing PFs through quality changes during processing and storage of prepared dishes. Currently, improving the quality and extending the shelf life of prepared dishes through thermal and non-thermal processing are the main modes of action of PFs. Most PFs show good potential in handing prepared dishes, but may also react poorly to some prepared dishes. In addition, the difficulty of precise control of processing conditions has led to research mostly at the laboratory stage, but as physical technology continues to break through, more PFs and multi-physical field will be promoted for commercial use in the future. This review contributes to a deeper understanding of the effect of PFs on prepared dishes, and provides theoretical reference and practical basis for future processing research in the development of various enhanced PFs.


Prepared dishes are classified according to the degree of processing.Physical fields are classified and described according to different physical methods.The application of efficient physical fields to prepared dishes is described.The application of efficient physical fields and its combination in food processing is prospected.

10.
J Mater Sci Mater Med ; 34(1): 6, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36586045

RESUMO

Electrospinning is a promising technique for preparing bioartificial blood vessels. Nanofibers prepared by electrospinning can simulate the structure of extracellular matrix to promote cell adhesion and proliferation. However, thorn-like protrusions can appear as defects on electrospun scaffolds and coaxial electrospun nanofibers often have no clear core/shell structure, which can seriously affect the quality of bioartificial blood vessels. To address these problems, Tween 80 is added to the electrospinning solution, which results in a stable Taylor cone, eliminates the thorn-like protrusions on electrospun bioartificial blood vessels, and reduces interfacial effects due to different core/shell solutions during coaxial electrospinning. Simulations, biomechanical tests, and in vivo studies were performed. The results demonstrate the excellent mechanical properties and biocompatibility of the bioartificial blood vessel. This research provides a useful reference for optimizing the electrospinning process for fabricating bioartificial blood vessels.


Assuntos
Nanofibras , Alicerces Teciduais , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Polissorbatos , Poliésteres/química , Nanofibras/química
11.
Pharm Dev Technol ; 27(1): 1-8, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34895029

RESUMO

Central nervous system infectious disease caused by the multidrug-resistant Acinetobacter baumannii (AB) seriously threatens human life in clinic. Tigecycline has good sensitivity in killing AB, but due to its wide tissue distribution and blood-brain barrier, concentration in cerebrospinal fluid is low, therefore, the clinical effect is limited. Herein, we designed micro-bubbled tigecycline, aimed to enhance its anti-MDRAB effects under ultrasound. The lipid microbubbles with different ratios of lipids to drugs (a ratio of 10:1, 20:1, and 40:1) were prepared by the mechanical shaking method. The morphology, zeta potential and particle size of microbubbles were tested to screen out the much better formulation. Encapsulation efficiency and drug loading amount were determined by ultracentrifugation combined with high-performance liquid chromatography. Then the in vitro antibacterial activity against AB was conducted using the selected ultrasound-activated microbubble. Results showed the selected microbubbles with high encapsulation efficiency and good stability. The mechanical shaking method is feasible for preparation of drug-loaded and ultrasound-activated lipid microbubbles. Using 0.2 mg/mL microbubbles, combined with 1 MHz, 2.5 W/cm2 and 1 min of ultrasound exhibited a potent anit-AB in vitro. This study indicates that tigecycline treatment in form of ultrasound-activated microbubble is a promising strategy against AB infections.


Assuntos
Antibacterianos , Microbolhas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Humanos , Tigeciclina/farmacologia
12.
J Environ Sci (China) ; 118: 147-157, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35305764

RESUMO

Different N and P fractions in microcosm incubation experiment was measured using high-resolution in-situ Peeper and DGT techniques combining with sequential extraction procedure. The results showed the synchronous desorption and release of PO43-, S2- and Fe2+ from the solid soil-originated sediment. This trend indicated that the significant reduction of Fe-P and SO42- occurred in the pore water during the inundation. The concentrations of PO43- in the overlying water and pore water increased to more than 0.1 and 0.2 mg/L at the beginning of the incubation experiment. Decreased NO3-concentrations from more than 1.5 mg/L to less than 0.5 mg/L combining with increasing NH4+ concentrations from less than 1 mg/L to more than 5 mg/L suggested the remarkable NO3- reduction via dissimilatory nitrate reduction to ammonia (DNRA) pathway over time. High NH4+ concentrations in the pore water aggravated the release of Fe2+ through reduction of Fe(III)-P as electric acceptors under anaerobic conditions. This process further stimulated the remarkable releasing of labile PO43- from the solid phase to the solution and potential diffusion into overlying water. Additionally, high S2- concentration at deeper layer indicated the reduction and releasing of S2- from oxidation states, which can stimulated the NO3- reduction and the accumulation of NH4+ in the pore water. This process can also provoke the reduction of Fe-P as electric acceptors following the release of labile PO43- into pore water. Generally, inundation potentially facilitate the desorption of labile P and attention should be paid during the reclaiming lake from polder.


Assuntos
Fósforo , Poluentes Químicos da Água , Sedimentos Geológicos , Ferro/análise , Lagos , Nitrogênio , Solo , Poluentes Químicos da Água/análise
13.
Epilepsia ; 61(5): 984-994, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32314372

RESUMO

OBJECTIVE: Insulo-opercular seizures are characterized by diverse semiology, related to the insula's multiple functional roles and extensive connectivity. We aimed to identify semiologic subgroups and correlate these with insulo-opercular subregions based on connectional architecture. METHODS: We retrospectively collected a large series of 37 patients with insulo-opercular seizures explored by stereoelectroencephalography (SEEG) from three epilepsy centers. A new human brain atlas (Brainnetome Atlas, BNA) based on both anatomic and functional connections was employed to segment insulo-opercular cortex. Semiology and SEEG changes were carefully reviewed and quantified. Principal component analysis and cluster analysis were used to correlate semiologic characteristics with insulo-opercular subregions. RESULTS: Four main semiologic subgroups were identified, organized along an anteroventral to posterodorsal axis based on BNA. Group 1 was characterized by epigastric sensation and/or integrated gestural motor behaviors with or without feelings of fear or rage, involving the anteroventral insular regions and mesial temporal lobes. Group 2 was characterized by auditory sensations and symmetric proximal/axial tonic signs involving the posteroventral temporal operculum. The characteristics of group 3 were orofacial and laryngeal signs, involving the intermediate insulo-opercular regions. The features of group 4 were somatosensory signs followed by nonintegrated gestural motor behaviors and/or asymmetric tonic signs involving the posterodorsal insulo-opercular regions with propagation to the mesial frontal lobes. Thus anteroventral seizure organizations predominantly showed limbic system semiology, whereas more posterodorsal regions were associated with semiology involving mainly the sensorimotor system. Subjective symptoms proved to be particularly discriminating factors. SIGNIFICANCE: Insulo-opercular seizures can be categorized in terms of clinical semiology and correlate with connectional architecture subregions along an anteroventral-posterodorsal axis in line with the cytoarchitectonic gradient rather than the gyral anatomy of the insula cortex. This provides new insights into facilitating differential diagnosis and presurgical localization but also highlights the importance of considering connectional architecture in determining neural correlates of complex semiologic patterns.


Assuntos
Córtex Cerebral/patologia , Epilepsia do Lobo Frontal/patologia , Vias Neurais/patologia , Convulsões/patologia , Adolescente , Córtex Cerebral/fisiopatologia , Eletroencefalografia , Epilepsia do Lobo Frontal/classificação , Epilepsia do Lobo Frontal/fisiopatologia , Feminino , Humanos , Masculino , Vias Neurais/fisiopatologia , Análise de Componente Principal , Estudos Retrospectivos , Convulsões/classificação , Convulsões/etiologia , Convulsões/fisiopatologia
14.
Anal Bioanal Chem ; 412(19): 4725-4737, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32476035

RESUMO

This study was based on the specific binding ability of magnetic molecularly imprinted polymers (MMIPs) combined with a high-performance liquid chromatography-fluorescence detector (HPLC-FLD) for the rapid determination of zearalenone (ZEN) in cereals. A novel magnetic molecularly imprinted polymer was prepared by surface imprinting technology. Warfarin was used as a virtual template, 3-aminopropyl triethoxysilane (APTES) was used as the functional monomer, and tetraethyl orthosilicate (TEOS) was used as the cross-linking agent. Analysis by a vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) showed that MMIPs were prepared with a particle size about 450 nm, the imprinted molecular layer accounting for 10.7% of the total mass, and saturation magnetization of about 34.54 emu/g. The maximum adsorption capacity (Qmax) of the thermodynamic and kinetic adsorption experiments were 13.90 mg/g and 8.71 mg/g, respectively. The Langmuir model showed that the binding sites were uniformly distributed on the surface of the MMIPs. The Scatchard analysis showed that MMIPs had two types of binding sites with Qmax of 8.22 mg/g and 15.37 mg/g, respectively. In actual sample detection, the limit of detection (LOD) and limit of quantification (LOQ) were 0.4 ng/kg and 0.9 ng/kg, respectively. The sample recovery rate was 90.56-99.96%, the daytime stability was 1.35-2.87%. These results showed that MMIPs had good performance in selectively identifying ZEN and were suitable for determining ZEN in cereals.


Assuntos
Grão Comestível/química , Nanopartículas de Magnetita/química , Polímeros Molecularmente Impressos/química , Zearalenona/análise , Contaminação de Alimentos/análise , Impressão Molecular/métodos , Dióxido de Silício/química
15.
Cereb Cortex ; 29(2): 517-528, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29342237

RESUMO

Previous studies have shown insular activations involving sensory, motor, and affective processing. However, the functional roles of subdivisions within the human insula are still not well understood. In the present study, we used intracranial electroencephalography and electrical cortical stimulation to investigate the causal roles of subdivisions of the insula in auditory emotion perception in epilepsy patients implanted with depth electrodes in this brain region. The posterior and the anterior subdivisions of the human insula, identified based on structural and functional analyses, showed distinct response properties to auditory emotional stimuli. The posterior insula showed auditory responses that resemble those observed in Heschl's gyrus, whereas the anterior insula (AI) responded to the emotional contents of the auditory stimuli in a similar way as observed in the amygdala. Furthermore, the degree of the differentiation between various emotion types increased from the posterior to the AI. Our findings suggest different roles played by the two regions of the human insula and a transformation from sensory to affective representations in auditory modality along the posterior-to-anterior axis in the human insula.


Assuntos
Percepção Auditiva/fisiologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Emoções/fisiologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Estimulação Acústica/métodos , Adolescente , Adulto , Imagem de Tensor de Difusão/métodos , Eletrocorticografia/métodos , Epilepsia/diagnóstico por imagem , Epilepsia/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Epilepsy Behav ; 91: 59-67, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30269938

RESUMO

OBJECTIVE: The present study investigated the electroclinical features and epileptogenic networks of parietal operculum seizures (POS) by using stereoelectroencephalography (SEEG) intracerebral recordings. METHODS: Comprehensive presurgical evaluation data of seven patients with drug-resistant epilepsy with POS were analyzed retrospectively. Stereoelectroencephalography-recorded seizures were processed visually and quantitatively by using epileptogenicity mapping (EM), which has been proposed to ergonomically quantify the epileptogenicity of brain structures with a neuroimaging approach. RESULTS: Six patients reported initial somatosensory or viscerosensitive symptoms. Ictal clinical signs comprised frequently nocturnal hypermotor seizures and contralateral focal motor seizures, including tonic, tonic-clonic, or dystonic seizures of the face and limbs. Interictal and ictal scalp EEG provided information regarding lateralization in the majority of patients, but the discharges were widely distributed over perisylvian or "rolandic-like" regions and the vertex. Furthermore, two subgroups of epileptogenic network organization were identified within POS by SEEG, visually and quantitatively, using an EM approach: group 1 (mesial frontal/cingulate networks) was observed in three patients who mainly exhibited hypermotor seizures; group 2 (perisylvian networks) was observed in four patients who mainly exhibited contralateral focal motor seizures. CONCLUSION: This study indicated that POS could be characterized by initial specific somatosensory sensations, followed by either frequently nocturnal hypermotor seizures or contralateral focal motor seizures. The distinctive seizure semiology depended on the organization of two primary epileptogenic networks. This article is part of the Special Issue "Individualized Epilepsy Management: Medicines, Surgery and Beyond.


Assuntos
Epilepsia Resistente a Medicamentos/fisiopatologia , Eletroencefalografia/métodos , Rede Nervosa/fisiopatologia , Lobo Parietal/fisiopatologia , Convulsões/fisiopatologia , Lobo Temporal/fisiopatologia , Adulto , Criança , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Feminino , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/cirurgia , Estudos Retrospectivos , Convulsões/diagnóstico por imagem , Convulsões/cirurgia , Técnicas Estereotáxicas , Lobo Temporal/diagnóstico por imagem
17.
J Liposome Res ; 29(2): 133-141, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30022692

RESUMO

The purpose of this study was to optimize the preparation conditions of podophyllotoxin liposomes (PPT-Lips), and to investigate their effects on PC3 cells. PPT-Lips were prepared by using a thin-film dispersion method. In order to achieve maximum drug encapsulation efficiency (EE), the process and formulation variables were optimized by response surface methodology (RSM). The optimum preparation conditions were cholesterol to lecithin ratio of 3.6:40 (w/w), lipid to drug ratio of 15.8:1 (w/w), and the ultrasonic intensity of 35% (total power of 400 W). The experimental EE of PPT-Lips was 90.425%, which was consistent with the theoretically predicted value. The characterization studies showed that PPT-Lips were well-dispersible spherical particles with an average size of 106 nm and a zeta potential of -10.1 mV. A gradual and time-dependent pattern of PPT from liposomes was found in in vitro drug release with a cumulative release amount up to 70.3% in 24 h. Results of cell viability experiments on PC3 cells demonstrated that PPT-Lips exhibited more effective anticancer activity in comparison with free PPT. Therefore, PPT-Lips represent an efficient and promising drug delivery system for PPT.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Lipossomos/química , Nanopartículas/química , Podofilotoxina/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Colesterol/química , Cromatografia Líquida de Alta Pressão , Liberação Controlada de Fármacos , Humanos , Lecitinas/química , Masculino , Células PC-3 , Podofilotoxina/administração & dosagem
18.
Neuroimage ; 181: 414-429, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30025851

RESUMO

In patients with pharmaco-resistant focal epilepsies investigated with intracranial electroencephalography (iEEG), direct electrical stimulations of a cortical region induce cortico-cortical evoked potentials (CCEP) in distant cerebral cortex, which properties can be used to infer large scale brain connectivity. In 2013, we proposed a new probabilistic functional tractography methodology to study human brain connectivity. We have now been revisiting this method in the F-TRACT project (f-tract.eu) by developing a large multicenter CCEP database of several thousand stimulation runs performed in several hundred patients, and associated processing tools to create a probabilistic atlas of human cortico-cortical connections. Here, we wish to present a snapshot of the methods and data of F-TRACT using a pool of 213 epilepsy patients, all studied by stereo-encephalography with intracerebral depth electrodes. The CCEPs were processed using an automated pipeline with the following consecutive steps: detection of each stimulation run from stimulation artifacts in raw intracranial EEG (iEEG) files, bad channels detection with a machine learning approach, model-based stimulation artifact correction, robust averaging over stimulation pulses. Effective connectivity between the stimulated and recording areas is then inferred from the properties of the first CCEP component, i.e. onset and peak latency, amplitude, duration and integral of the significant part. Finally, group statistics of CCEP features are implemented for each brain parcel explored by iEEG electrodes. The localization (coordinates, white/gray matter relative positioning) of electrode contacts were obtained from imaging data (anatomical MRI or CT scans before and after electrodes implantation). The iEEG contacts were repositioned in different brain parcellations from the segmentation of patients' anatomical MRI or from templates in the MNI coordinate system. The F-TRACT database using the first pool of 213 patients provided connectivity probability values for 95% of possible intrahemispheric and 56% of interhemispheric connections and CCEP features for 78% of intrahemisheric and 14% of interhemispheric connections. In this report, we show some examples of anatomo-functional connectivity matrices, and associated directional maps. We also indicate how CCEP features, especially latencies, are related to spatial distances, and allow estimating the velocity distribution of neuronal signals at a large scale. Finally, we describe the impact on the estimated connectivity of the stimulation charge and of the contact localization according to the white or gray matter. The most relevant maps for the scientific community are available for download on f-tract. eu (David et al., 2017) and will be regularly updated during the following months with the addition of more data in the F-TRACT database. This will provide an unprecedented knowledge on the dynamical properties of large fiber tracts in human.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Conectoma/métodos , Eletrocorticografia/métodos , Epilepsia/diagnóstico por imagem , Potenciais Evocados/fisiologia , Adolescente , Adulto , Atlas como Assunto , Córtex Cerebral/fisiopatologia , Criança , Pré-Escolar , Bases de Dados Factuais , Epilepsia/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Adulto Jovem
19.
BMC Neurol ; 18(1): 110, 2018 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-30103717

RESUMO

BACKGROUND: Seizures arising from the precuneus are rare, and few studies have aimed at characterizing the clinical presentation of such seizures within the anatomic context of the frontoparietal circuits. We aimed to characterize the electrophysiological properties and clinical features of seizures arising from the precuneus based on data from stereoelectroencephalography (SEEG). METHODS: The present retrospective study included 10 patients with medically intractable epilepsy, all of whom were diagnosed with precuneal epilepsy via stereoelectroencephalography (SEEG) at Yuquan Hospital and Xuan Wu Hospital between 2014 and 2016. Clinical semiology, scalp electroencephalography (EEG) findings, magnetic resonance images (MRI), and positron emission tomography (PET) images were analyzed during phase I preoperative evaluations. Following electrode implantation, the semiological sequence, ictal SEEG evolution, and anatomy of the relevant brain structures were analyzed for each seizure. RESULTS: Seven of ten patients reported auras, including body image disturbance (2/7), vestibular responses (2/7), somatosensory auras (1/7), visual auras (1/7), and non-specific auras (1/7). Primary motor manifestations included bilateral asymmetric tonic seizures (BATS) (7/10) and hypermotor seizures (HMS) (3/10). In one patient, epileptiform discharge on interictal EEG occurred ipsilateral to the side of the epileptogenic zone (EZ). Discharge was non-lateralized in the remaining nine patients. In six patients, interictal EEG signals were primarily localized in the temporal-parietal-occipital area. In two patients, ictal onset occurred ipsilateral to the EZ, which was mainly located in the temporal-parietal-occipital area. Two patterns of seizure spread were observed. The first pattern was characterized by BATS activity with ictal spread to the supplementary motor area (SMA), paracentral lobule (PCL), precentral gyrus (PrCG), or postcentral gyrus (PoCG). The second pattern was characterized by HMS activity with ictal spread to middle cingulate cortex (MCC) and posterior cingulate cortex (PCC). CONCLUSION: Aura type (e.g., body image disturbance and vestibular response), BATS, and HMS are the main indicators of precuneal epilepsy. Scalp EEG is of little use when attempting to localize precuneal seizures. Our findings indicate that the clinical characteristics of precuneal epilepsy vary among patients, and that the final electro-clinical phenotype depends on the pattern of seizure spread.


Assuntos
Eletroencefalografia/métodos , Lobo Parietal/fisiopatologia , Convulsões/fisiopatologia , Adolescente , Córtex Cerebral/fisiopatologia , Criança , Epilepsia Resistente a Medicamentos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Convulsões/diagnóstico por imagem , Adulto Jovem
20.
RSC Adv ; 14(14): 9472-9481, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516163

RESUMO

Quercetin (QCT) has a variety of pharmacological effects, such as antioxidant, antibacterial, anticancer, anticardiovascular and antiaging effects. However, its poor water solubility, stability and bioavailability limit its applications. The special structure of cyclodextrins and their derivatives with a hydrophobic inner cavity and hydrophilic outer wall can load a variety of hydrophobic drugs of a suitable size and shape, thereby improving the stability and solubility of these molecules. In this study, an inclusion complex of quercetin and sulfobutylether-ß-cyclodextrin was prepared. It was characterized via FT-IR, UV, 1H NMR, XRD, DSC, and SEM analysis, which revealed the successful formation of the inclusion complex. In vitro biological activity estimations were carried out and the results indicated that the inclusion complex displayed higher antioxidative and antibacterial properties compared with free QCT. In addition, the mechanisms of inclusion were explored using 1H NMR analysis and docking calculations, thus providing a theoretical basis for obtaining an inclusion complex.

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