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1.
Food Res Int ; 190: 114630, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945583

RESUMO

Food bolus is the major outcome of oral processing of foods. Its structure and properties are crucial for safe swallowing and subsequent gastric digestion. However, collecting the ready-to-swallow bolus for further analysis in either normal or deficient human subjects is difficult, regulatorily or practically. Here, a novel in vitro bio-inspired oral mastication simulator (iBOMS-Ⅲ) was developed to be capable of replicating food boluses comparable to those in vivo. Cooked rice and roasted peanuts were used as the model foods (soft and hard) respectively. Particle size distribution, moisture content and rheology of the food boluses produced in the iBOMS-Ⅲ were assessed. A conventional food blender was also employed as a non-consequential comparation. Eighteen healthy young volunteers of the ages from 20-30 years (10 male and 8 female) were invited to provide the in vivo data. For cooked rice boluses produced by the iBOMS-Ⅲ with 10, 12, 14, and 20 chewing number of cycles, the moisture content exhibited minimal variation (68.3-68.8 wt%), aligning closely with values obtained from the average value of the human subjects (67.5 wt%). Similarly, the boluses from roasted peanut displayed similar moisture contents across masticatory number of cycles (36, 40, and 44 number of cycles), averaging at 35.3 %, mirroring the average in vivo results (33.8 wt%). Furthermore, the shear viscosity of both cooked rice and roasted peanut boluses exhibited minimal variations with iBOMS-Ⅲ chewing number of cycles. The particle size distributions of the boluses produced with 14 and 44 chewing number of cycles matched well with the in vivo data for cooked rice and roasted peanuts, with median particle size (d50) being 1.07 and 0.78 mm, respectively. The physical properties of the food boluses collected from the food blender, with varying grinding times, differed significantly. This study demonstrates the value of the iBOMS-Ⅲ in achieving realistic boluses with two very different food textures.


Assuntos
Arachis , Culinária , Mastigação , Oryza , Tamanho da Partícula , Mastigação/fisiologia , Oryza/química , Humanos , Masculino , Adulto , Adulto Jovem , Feminino , Arachis/química , Culinária/métodos , Reologia , Deglutição/fisiologia , Digestão/fisiologia
2.
J Environ Manage ; 362: 121260, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38833924

RESUMO

Accurate multi-step ahead flood forecasting is crucial for flood prevention and mitigation efforts as well as optimizing water resource management. In this study, we propose a Runoff Process Vectorization (RPV) method and integrate it with three Deep Learning (DL) models, namely Long Short-Term Memory (LSTM), Temporal Convolutional Network (TCN), and Transformer, to develop a series of RPV-DL flood forecasting models, namely RPV-LSTM, RPV-TCN, and RPV-Transformer models. The models are evaluated using observed flood runoff data from nine typical basins in the middle Yellow River region. The key findings are as follows: Under the same lead time conditions, the RPV-DL models outperform the DL models in terms of Nash-Sutcliffe efficiency coefficient, root mean square error, and relative error for peak flows in the nine typical basins of the middle Yellow River region. Based on the comprehensive evaluation results of the train and test periods, the RPV-DL model outperforms the DL model by an average of 2.82%-22.21% in terms of NSE across nine basins, with RMSE and RE reductions of 10.86-28.81% and 36.14%-51.35%, respectively. The vectorization method significantly improves the accuracy of DL flood forecasting, and the RPV-DL models exhibit better predictive performance, particularly when the lead time is 4h-6h. When the lead time is 4-6h, the percentage improvement in NSE is 9.77%, 15.07%, and 17.94%. The RPV-TCN model shows superior performance in overcoming forecast errors among the nine basins. The research findings provide scientific evidence for flood prevention and mitigation efforts in river basins.


Assuntos
Aprendizado Profundo , Inundações , Previsões , Rios , Algoritmos , Modelos Teóricos
3.
Sci Data ; 11(1): 500, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750096

RESUMO

Here we presented an electrophysiological dataset collected from layer V of the primary motor cortex (M1) and the corresponding behavior dataset from normal and hemi-parkinson rats over 5 consecutive weeks. The electrophysiological dataset was constituted by the raw wideband signal, neuronal spikes, and local field potential (LFP) signal. The open-field test was done and recorded to evaluate the behavior variation of rats among the entire experimental cycle. We conducted technical validation of this dataset through sorting the spike data to form action potential waveforms and analyzing the spectral power of LFP data, then based on these findings a closed-loop DBS protocol was developed by the oscillation activity response of M1 LFP signal. Additionally, this protocol was applied to the hemi-parkinson rat for five consecutive days while simultaneously recording the electrophysiological data. This dataset is currently the only publicly available dataset that includes longitudinal closed-loop DBS recordings, which can be utilized to investigate variations of neuronal activity within the M1 following long-term closed-loop DBS, and explore additional reliable biomarkers.


Assuntos
Estimulação Encefálica Profunda , Córtex Motor , Animais , Ratos , Córtex Motor/fisiologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Potenciais de Ação , Comportamento Animal , Fenômenos Eletrofisiológicos , Neurônios/fisiologia
4.
J Funct Biomater ; 14(6)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37367286

RESUMO

Investigating the effect of nanomedicines on cancer cell behavior in three-dimensional (3D) platforms is beneficial for evaluating and developing novel antitumor nanomedicines in vitro. While the cytotoxicity of nanomedicines on cancer cells has been widely studied on two-dimensional flat surfaces, there is little work using 3D confinement to assess their effects. This study aims to address this gap by applying PEGylated paclitaxel nanoparticles (PEG-PTX NPs) for the first time to treat nasopharyngeal carcinoma (NPC43) cells in 3D confinement consisting of microwells with different sizes and a glass cover. The cytotoxicity of the small molecule drug paclitaxel (PTX) and PEG-PTX NPs was studied in microwells with sizes of 50 × 50, 100 × 100, and 150 × 150 µm2 both with and without a concealed top cover. The impact of microwell confinement with varying sizes and concealment on the cytotoxicity of PTX and PEG-PTX NPs was analyzed by assessing NPC43 cell viability, migration speed, and cell morphology following treatment. Overall, microwell isolation was found to suppress drug cytotoxicity, and differences were observed in the time-dependent effects of PTX and PEG-PTX NPs on NPC43 cells in isolated and concealed microenvironments. These results not only demonstrate the effect of 3D confinement on nanomedicine cytotoxicity and cell behaviors but also provide a novel method to screen anticancer drugs and evaluate cell behaviors in vitro.

5.
Ecotoxicol Environ Saf ; 262: 115151, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37356396

RESUMO

Lipids are main energy source for insects reproduction, which are becoming emerging target for pest management. Azadirachtin (AZA) is a multi-targeted and promising botanical insecticide, but its reproduction toxicity mechanism related to lipids metabolism is poorly understood. Here, we applied lipidomic and transcriptomic to provide a comprehensive resource for describing the effect of AZA on lipids remodeling in ovary of Spodoptera litura. The results showed that AZA exposure obviously altered the contents of 130 lipids subclasses (76 upregulated and 54 downregulated). In detail, AZA exposure changed the length and saturation degrees of fatty acyl chain of most glycerolipid, phospholipid and sphingolipid as well as the expression of genes related to biosynthesis of unsaturated fatty acids and fatty acids elongation. Besides, following the abnormal lipids metabolism, western blot analysis suggested that AZA induce insulin resistance-like phenotypes by inhibiting insulin receptor substrates (IRS) /PI3K/AKT pathway, which might be responsible for the ovary abnormalities of S. litura. Collectively, our study provided insights into the lipids metabolism event in S. litura underlying AZA exposure, these key metabolites and genes identified in this study would also provide important reference for pest control in future.

6.
J Insect Sci ; 23(2)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37052365

RESUMO

Endosymbionts live symbiotically with insect hosts and play important roles in the evolution, growth, development, reproduction, and environmental fitness of hosts. Weevils are one of the most abundant insect groups that can be infected by various endosymbionts, such as Sodalis, Nardonella, and Wolbachia. The sweet potato weevil, Cylas formicarius (Coleoptera: Brentidae), is a notorious pest in sweet potato (Ipomoea batatas L.) cultivation. Currently, little is known about the presence of endosymbionts in C. formicarius. Herein, we assessed the endosymbiont load of a single geographic population of C. formicarius. The results showed that Nardonella and Rickettsia could infect C. formicarius at different rates, which also varied according to the developmental stages of C. formicarius. The relative titer of Nardonella was significantly related to C. formicarius developmental stages. The Nardonella-infecting sweet potato weevils were most closely related to the Nardonella in Sphenophorus levis (Coleoptera, Curculionidae). The Rickettsia be identified in bellii group. These results preliminarily revealed the endosymbionts in C. formicarius and helped to explore the diversity of endosymbionts in weevils and uncover the physiological roles of endosymbionts in weevils.


Assuntos
Besouros , Ipomoea batatas , Gorgulhos , Animais , Reprodução
7.
Lab Chip ; 23(3): 511-524, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36632832

RESUMO

The three-dimensional (3D) structure of the extracellular matrix and cell-cell contacts are two important cues to altering cell migration behavior and the tumor formation process. In this work, we designed and fabricated microwell arrays with a grating-patterned bottom in polydimethylsiloxane platforms to systematically study the effects of confinement, changes in topography, and cell-cell contacts on the migration behavior of nasopharyngeal carcinoma (NPC43) and immortalized nasopharyngeal epithelial (NP460) cells by time-lapse imaging. When two types of cells were co-cultured in microwells, the migration speed and spreading area of NPC43 cells were significantly increased, which might be attributed to the heterotypic cell-cell contacts with NP460 cells. On a flat surface, NPC43 cells could not form clusters due to the frequent interruptions by the active movements of NP460 cells. However, in 3D microwell arrays, clusters of NPC43 cells formed on the bottom surface while the majority of NP460 cells migrated onto the sidewalls. These cell clusters could be further processed to form spheroids for drug screening. These results also revealed that the 3D microenvironments and cell-cell contacts could have significant implications for NPC cell migration and initiation of tumor formation, which will provide insight for NPC progression and dissemination.


Assuntos
Células Epiteliais , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/metabolismo , Técnicas de Cocultura , Matriz Extracelular , Neoplasias Nasofaríngeas/metabolismo , Microambiente Tumoral
8.
Front Physiol ; 13: 943205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812325

RESUMO

Ribosomal proteins (Rps) are indispensable in ribosome biogenesis and protein synthesis, which tightly correlate with cell growth and proliferation in different physiological processes across species. Up to now, genes coding for Rps have been identified and studied in many species, however, their information still remains elusive in many insect species, especially in Spodoptera litura. In this study, 81 Rp genes were identified from S. litura genome and were mapped to their positions on the chromosomes. In addition, their physical and chemical properties, gene structure, phylogenetic relationships, targeted microRNAs were also analyzed. Gene ontology analysis disclosed that Rp genes were closely associated with processes related to ribosome biosynthesis, proteins translation processing, molecular binding activities. The quantitative real-time PCR (qRT-PCR) revealed expression profiles of Rp genes varied in different stages of oogenesis, and found that most Rp genes accumulated in previtellogenesis stage. This study described the comprehensive genome-wide analysis of Rp gene family in agricultural pests, which provided foundation for further characterizing the roles of Rps in oogenesis of insects, and some Rp genes may further serve as targets for innovative pest control.

9.
Ecotoxicol Environ Saf ; 237: 113548, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35487172

RESUMO

Azadirachtin is one of the most successful botanical pesticides in agricultural pest control. To build a repertoire of proteins and pathways in response to azadirachtin exposure during ovarian development, iTRAQ-based comparative proteomic was conducted. 1423 and 1686 proteins were identified as differentially accumulated proteins (DAPs) by comparing the protein abundance in adult ovary with that in pupal ovary under normal and azadirachtin exposure condition, respectively. Bioinformatics analysis indicated that pupae-to-adult transition requires proteins related to proteasome and branched chain amino acids (BCAAs) degradation for ovary development. Azadirachtin exposure strongly affected glycosylation-related pathway. And proteins related to vitamin B6 synthesis were necessary for ovary development under normal and AZA-exposure condition. RNAi assays confirmed the essential roles of DAPs related to glycosylation and vitamin B6 synthesis in moth growth and ovary development. The results enhance our understanding of the molecular regulatory network for ovary development and provide valuable resources for using AZA-responsive proteins to develop novel bio-rational insecticides.


Assuntos
Inseticidas , Proteômica , Animais , Feminino , Inseticidas/metabolismo , Inseticidas/toxicidade , Larva , Limoninas , Pupa/genética , Spodoptera , Vitamina B 6/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-34705653

RESUMO

Retinal prostheses are biomedical devices that directly utilize electrical stimulation to create an artificial vision to help patients with retinal diseases such as retinitis pigmentosa. A major challenge in the microelectrode array (MEA) design for retinal prosthesis is to have a close topographical fit on the retinal surface. The local retinal topography can cause the electrodes in certain areas to have gaps up to several hundred micrometers from the retinal surface, resulting in impaired, or totally lost electrode functions in specific areas of the MEA. In this manuscript, an MEA with dynamically controlled electrode positions was proposed to reduce the electrode-retina distance and eliminate areas with poor contact after implantation. The MEA prototype had a polydimethylsiloxane and polyimide hybrid flexible substrate with gold interconnect lines and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate electrodes. Ring shaped counter electrodes were placed around the main electrodes to measure the distance between the electrode and the model retinal surface in real time. The results showed that this MEA design could reduce electrode-retina distance up to [Formula: see text] with 200 kPa pressure. Meanwhile, the impedance between the main and counter electrodes increased with smaller electrode-model retinal surface distance. Thus, the change of electrode-counter electrode impedance could be used to measure the separation gap and to confirm successful electrode contact without the need of optical coherence tomography scan. The amplitude of the stimulation signal on the model retinal surface with originally poor contact could be significantly improved after pressure was applied to reduce the gap.


Assuntos
Próteses Visuais , Estimulação Elétrica , Eletrodos Implantados , Humanos , Microeletrodos , Retina , Tomografia de Coerência Óptica
11.
Lab Chip ; 19(14): 2466-2475, 2019 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-31225540

RESUMO

Natural killer (NK) cells are lymphocytes which play an important role in the immune system by recognizing and killing potentially malignant cells without antigen sensitization, and could be utilized in cancer therapy. NK cell migration is an essential process to find and kill target cells, which is well known to be driven by the chemotaxis effect. NK cells also experience a topographical effect induced by the extracellular matrix (ECM) during their migration. However, topographical effects on NK cell locomotion in three dimensional (3D) environments are not well studied yet. In this work, polydimethylsiloxane based platforms containing microchannels with different types of perturbations and decorated with various surface patterns were fabricated to systematically study the topographical effect on NK cell migration with and without the chemotaxis effect. The results showed that perturbation sites in channels induced pauses and reversals in chemotaxis driven NK cell migration. Surface topography such as gratings in confined environments could introduce directional preference to NK cell movement even without chemoattractants. These findings showed that NK cell migration could be controlled by contact guidance, which provides future possibility to manipulate NK cell migration in controlled in vitro bioengineering systems. Results in this study showed that the complex topography of 3D microenvironments in the ECM could have significant effects on NK cell migration in different tissues and organs, and provided insight for explaining the dynamics of NK cell activities in clinical experiments.


Assuntos
Movimento Celular , Células Matadoras Naturais/citologia , Dispositivos Lab-On-A-Chip , Quimiotaxia , Difusão , Dimetilpolisiloxanos/química , Humanos , Cinética , Células MCF-7 , Imagem Molecular , Nylons/química
12.
Front Immunol ; 8: 998, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28861090

RESUMO

Natural killer (NK) cells serve an important role in immune system by recognizing and killing the potentially malignant cells without antigen sensitization, and could be promising in cancer therapy. We have designed and fabricated microwell arrays with microchannel connections in polydimethylsiloxane (PDMS) substrates to study the interaction dynamics of NK-92MI cells with MCF7 breast cancer cells using time-lapse imaging by fluorescence microscopy for 15 h. Although cell seeding density was the same, NK cell cytotoxicity was found to be higher in larger microwells, which is manifested as increased target death ratio from 13.7 ± 3.1 to 46.3 ± 3.3% and shorter triggering time of first target lysis from 502 ± 49 to 391 ± 63 min in 150 µm × 150 µm microwells comparing to 50 µm × 50 µm wells in 15 h. Mirochannel connection between adjacent microwells of the same size increased the overall target death ratio by >10%, while connection between microwells of different sizes led to significantly increased target death ratio and delayed first target lysis in smaller microwells. Our findings reveal unique cell interaction dynamics, such as initiation and stimulation, of NK cell cytotoxicity in a confined microenvironment, which is different from population-based study, and the results could lead to a better understanding of the dynamics of NK cell cytotoxicity.

13.
J Ethnopharmacol ; 127(1): 196-9, 2010 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-19799978

RESUMO

AIM OF THE STUDY: To assess the effectiveness of the traditional Chinese herb Phellodendron amurense in treating urological disorders. MATERIALS AND METHODS: Prostate smooth muscle relaxant activity of an extract from the bark of Phellodendron amurense was tested on contractions of isolated rat prostate gland induced by electrical nerve stimulation and direct muscle stimulation. RESULTS: Electrical field stimulation (0.5 ms, 60V, 1-20 Hz) induced nerve mediated contractions of isolated rat prostate were inhibited by Phellodendron amurense extract dissolved in either dimethylsulfoxide (DMSO), acetic acid or water (P

Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Contração Isométrica/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Phellodendron , Fitoestrógenos/farmacologia , Casca de Planta , Próstata/efeitos dos fármacos , Agonistas Adrenérgicos/farmacologia , Animais , Agonistas Colinérgicos/farmacologia , Estimulação Elétrica , Técnicas In Vitro , Masculino , Medicamentos sob Prescrição/farmacologia , Próstata/fisiologia , Hiperplasia Prostática/tratamento farmacológico , Agonistas Purinérgicos , Ratos , Ratos Sprague-Dawley
14.
Beijing Da Xue Xue Bao Yi Xue Ban ; 35(1): 37-40, 2003 Feb 18.
Artigo em Chinês | MEDLINE | ID: mdl-12920806

RESUMO

OBJECTIVE: To study the clinicopathological features, the histogenesis, and the correlation between the expressions of estrogen receptor(ER) and epidermal growth factor receptor(EGFR) in leiomyoma of the vagina. METHODS: The data of 26 patients with leiomyoma of the vagina were analyzed retrospectively, and S-P immunohistochemistry was used to detect smooth muscle actin(SMA), S-100 protein, CD34, ER and EGFR in the tumor tissues. RESULTS: All patients with leiomyoma of the vagina in this group were married women, with age ranging from 30 to 52 years (mean, 44.5 years). Leiomyoma of the vagina was slow in growth and occasionally recurred with borderline and malignant transformation. Immunohistochemical staining demonstrated to be strongly positive for SMA, and negative for S-100 protein and CD34 in all cases. Positive expression rates for ER and EGFR were 38.5 (10/26) and 34.6 (9/26) respectively. There was a significant positive correlation between the expressions of ER and EGFR (Fisher exact, P = 0.0023, r = 0.75). Resection of the tumor mass was an effective method to cure the disease. CONCLUSION: Leiomyoma of the vagina is a rare condition, which may be derived from stem cells of mesenchyma of the vagina differentiating towards smooth muscle. The estrogen hormone and EGF may play an important role in the development and growth of leiomyoma of the vagina. Follow-up is needed after operation for the patient with borderline tumor.


Assuntos
Leiomioma/patologia , Neoplasias Vaginais/patologia , Adulto , Antígenos CD34/análise , Receptores ErbB/análise , Feminino , Humanos , Imuno-Histoquímica , Leiomioma/química , Leiomioma/terapia , Pessoa de Meia-Idade , Receptores de Estrogênio/análise , Neoplasias Vaginais/química , Neoplasias Vaginais/terapia
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