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1.
Graefes Arch Clin Exp Ophthalmol ; 262(4): 1121-1129, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37999773

RESUMEN

PURPOSE: To explore the role of choroidopathy in diabetic retinopathy (DR) by investigating the correlation between alterations of choroidal vessel and photoreceptors during the early stage of DR. METHODS: We performed a cross-sectional comparison of diabetic patients without DR (NDR group; n=16) and those with mild nonproliferative diabetic retinopathy (NPDR group; n=39). Optical coherence tomography (OCT) images of choroidal vessel alterations and photoreceptor structures were evaluated using the choroidal vascularity index (CVI) and adjusted ellipsoid zone (EZ) reflectivity, respectively. To evaluate the function of cone photoreceptors, the fundamental, harmonic amplitudes, the parameters S and Rmp3 were calculated from the electroretinogram (ERG). These factors were compared between groups. The correlation between the CVI and parameters describing the function and structure of the photoreceptors was evaluated. RESULTS: The significant decrease was observed in the CVI in the NPDR group compared to the NDR group (0.67 ± 0.04 vs. 0.70 ± 0.06; p = 0.028), but not in the adjusted EZ reflectivity or ERG parameters. In NPDR group and merging the 2 groups, CVI was moderately positively correlated with the fundamental amplitude obtained by the flicker ERG (NPDR only: r = 0.506; p = 0.001; merge the 2 groups: r = 0.423; p = 0.001), which was regulated by the response of the cone photoreceptors. The CVI was positively and moderately correlated with the logS (NPDR only: r = 0.462; p = 0.003; merge the 2 groups: r = 0.355; p = 0.008), indicating the sensitivity of cone cell light transduction. CONCLUSION: Compared to eyes without DR, CVI decreased representing choroidal vascular changes in eyes with mild NPDR. These changes may be related to the functional impairment of cone photoreceptors, especially phototransduction sensitivity, as the DR develops.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Humanos , Retinopatía Diabética/diagnóstico , Estudios Transversales , Células Fotorreceptoras Retinianas Conos/fisiología , Electrorretinografía/métodos , Tomografía de Coherencia Óptica/métodos
2.
Anal Chem ; 95(36): 13586-13595, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37624148

RESUMEN

In this paper, we present a highly effective microfluidic emulsion system using an integrated microchannel plate (MCP), a porous glass membrane that is readily available and densely packs millions of through-microchannels, for high-throughput production of monodisperse droplets. The physical controls of droplet formation, including viscosity, flow rate, and pore size, have been extensively explored for optimum emulsification conditions. The performance of the device has been validated where monodisperse droplets with a narrow coefficient of variance (<5%) can be achieved at a dispersed phase flux of 3 mL h-1 from a piece of 4 × 4 mm2 MCP. The average droplet size is two times the nominal membrane pore diameter and thus can be easily controlled by choosing the appropriate membrane type. The preparation of hydrogel microspheres has also been demonstrated with a high throughput of 1.5 × 106 particles min-1. These microspheres with a uniform size range and rough surface morphology provide suitable bioenvironments and serve as ideal carriers for cell culture. Mouse fibroblasts are shown to be cultured on these 3D scaffolds with an average cell viability of over 96%. The cell attachment rate can reach up to 112 ± 7% in 24 h and the proliferation ability increases with the number of culture days. Furthermore, the device has been applied in the droplet digital polymerase chain reaction for absolute quantification of lung cancer-related PLAU genes. The detection limit achieved was noted to be 0.5 copies/µL with a dynamic range of 105 ranging from 1 × 102 to 1 × 106 copies/µL. Given the easy fabrication, robust performance, and simple operation, the emulsion system sets the stage for the laboratory's droplet-based assays and applications in tissue engineering.


Asunto(s)
Hidrogeles , Microfluídica , Animales , Ratones , Microesferas , Emulsiones , Vendajes
3.
Anim Biotechnol ; 34(1): 77-84, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34138682

RESUMEN

This study was conducted to examine the influence of uni and bilateral castration on growth performance and lipid metabolism in yellow cattle. Eighteen 9-month-old healthy yellow cattle (average body weight 184.03 ± 4.09 kg) were selected and divided into three groups: The uncastrated cattle (C), half castrated cattle (HC) and full castrated cattle (FC). The results showed that the growth rate of FC group was significantly reduced as compared to HC and C group, while the feed to gain ratio exhibited an opposite trend. The concentrations of triglycerides (TG), low-density lipoprotein cholesterol (LDL) and high-density lipoprotein (HDL) were increased significantly in FC group from day 60 to the end of the trial compared to HC and control groups. Serum testosterone concentration of FC group cattle was decreased from day 60 to 120 d of the trial compared to HC and control groups. The concentration of the lauric acid in FC cattle was significantly increased from the HC and control groups. In the FC group, the acetyl-CoA carboxylase alpha (ACACA), ACC and fatty acid synthase (FAS) gene expression levels were significantly higher compared to control and HC groups. Our results of this study suggest that bilateral castration increased the lipid metabolism and fatty acid composition compared to unilateral castrated and un-castrated cattle.HighlightsBilateral castration alters the growth performance in yellow cattle.Bilateral castration alters hormones levels and lipid metabolites levels in serum.Bilateral castration improves the lipid metabolism and fatty acid profile.


Asunto(s)
Ácidos Grasos , Metabolismo de los Lípidos , Bovinos , Animales , Metabolismo de los Lípidos/genética , Castración , Triglicéridos , Peso Corporal
4.
J Dairy Sci ; 106(2): 1351-1359, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36460498

RESUMEN

In this study, we aimed to classify 7 cow behavior patterns automatically with an inertial measurement unit (IMU) using a fully convolutional network (FCN) algorithm. Behavioral data of 12 cows were collected by attaching an IMU in a waterproof box on the neck behind the head of each cow. Seven behavior patterns were considered: rub scratching (leg), ruminating-lying, lying, feeding, self-licking, rub scratching (neck), and social licking. To simplify the data and compare classification performance with or without magnetometer data, the 9-axis IMU data were reduced using the square root of the sum of squares to develop 2 datasets. Comparing the classification accuracy of the 3 models using a window size of 64 with 6-axis data and a window size of 128 with both 6-axis and 9-axis data, the best overall accuracy (83.75%) was achieved using the FCN model with a window size of 128 (12.8 s) using all IMU data. This model achieved classification accuracies of 83.2, 96.5, 92.8, 98.1, 82.9, 87.2, and 45.2% for ruminating-lying, lying, feeding, rub scratching (leg), self-licking, rub scratching (neck), and social licking, respectively. As a sequence of varied and intensive movement, the classification accuracy of behavior patterns related to skin disease was lower; better classification of these behavior patterns could be achieved with full IMU data and a larger window size. In the future, additional data will take into account different data types, such as audio and video data, to further enhance performance. In addition, an adaptive sliding window size will be used to improve model performance.


Asunto(s)
Conducta Animal , Movimiento , Femenino , Bovinos , Animales , Algoritmos , Ingestión de Alimentos
5.
Nanotechnology ; 32(14): 140001, 2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33339008

RESUMEN

Here, a relative simpler and lower cost method, ion beam sputtering deposition was applied to fabricate diluted magnetic Mn x Ge1-x quantum dots (QDs). The effects of Ge-Mn co-deposition amount on the morphology and crystallization of Mn0.03Ge0.97 QDs were investigated systematically by employing the atomic force microscopy and Raman spectroscopy techniques. It can be seen that the morphology, density, and crystallinity of Mn0.03Ge0.97 QDs exhibit unique evolution processes with the increase of Ge-Mn co-sputtering amount. The optimal deposition amount for realizing well size-uniform, large-aspect-ratio, and high-density QDs is also determined. The unique evolution route of diluted magnetic semiconductor QDs and the amount of co-sputtering are also discussed sufficiently.

6.
Biomicrofluidics ; 18(1): 011303, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38362304

RESUMEN

The robust identification and quantification of various biomarkers is of utmost significance in clinical diagnostics and precision medicine. Fluorescent immunoassays are widely used and considered as a gold standard for biomarker detection due to their high specificity and accuracy. However, current commercial immunoassay tests suffer from limited detection sensitivity and complicated, labor-intensive operation procedures, making them impractical for point-of-care diagnosis, particularly in resource-limited regions. Recently, microfluidic immunoassay devices integrated with plasmonic nanostructures have emerged as a powerful tool for sensitive detection of biomarkers, addressing specific issues, such as integration schemes, easy operation, multiplexed detection, and sensitivity enhancement. In this paper, we provide a discussion on the recent advances in the plasmonic nanostructures integrated with microfluidic devices for fluorescent immunoassays. We shed light on the nanofabrication strategies and various fluidic designs for rapid, sensitive, and highly efficient sensing of antigens. Finally, we share our perspectives on the potential directions of these integrated devices for practical applications.

7.
J Colloid Interface Sci ; 675: 1080-1090, 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39018635

RESUMEN

Premature drug release in chemotherapy and hypoxic conditions in photodynamic therapy (PDT) are perplexing problems in tumor treatment. Thus, it is of great significance to develop the novel therapeutic system with controllable drug release and effective oxygen generation. Herein, a pH-responsive oxygen self-sufficient smart nanoplatform (named DHCCC), integrating hollow mesoporous silica nanoparticles (HMSNs), chitosan (CS), doxorubicin hydrochloride (DOX), chlorin e6 (Ce6) and catalase (CAT), is fabricated to enhance the tumor therapeutic efficacy efficiently through avoiding premature drug release and mitigating hypoxia of tumor microenvironment (TME). The drug DOX can be efficiently loaded into the HMSNs with large cavity and be controllable released because of the pH responsiveness of CS to the weak acidic TME, thereby elevating the chemotherapy efficacy. Meanwhile, CAT can catalyze the decomposition of endogenous hydrogen peroxide in situ generating oxygen to alleviate the hypoxia and enhance the PDT efficiency considerably. In vitro and in vivo results demonstrate that the combined chemo-photodynamic therapy based on the DHCCC nanoplatform exerts more effective antitumor efficacy than chemotherapy or PDT alone. The current study provides a promising inspiration to construct the pH-responsive oxygen self-sufficient smart nanomedicine with potentials to prevent premature drug leakage and overcome hypoxia for efficient tumor therapy.

8.
Biosens Bioelectron ; 213: 114499, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35772345

RESUMEN

In this paper, we report on an integrated microfluidic digital PCR system for rapid and high-performance absolute quantification of DNA at a single-molecular level. Microchannel plate (MCP), a highly porous glass membrane conventionally used as a particle multiplier in detectors, is demonstrated here as an ideal platform for the sample partition and high-fidelity DNA detection. The density of the microreactors reaches up to 1563 mm-2, with a total number of 25,000 chambers each in 100 pL volumes embedded in 4 × 4 mm2 MCP. This glass membrane consisting of highly-regular, densely-packed and high-aspect ratio microchannels is batch-fabricated through fiber-draw technology that requires no cumbersome lithography or etching process. The sidewalls, having a slight tilting angle with respect to the surface normal, can be functionalized with ZnO nanorods through one-step shadowing-based deposition without resorting to complicated solution-process or lithography. In this way, the required thermal cycling time for end-point detection has been reduced from 40 min to 25 min through plasmonic fluorescence enhancement compared to bare MCP without nanostructures. The digital PCR performance of our system has been validated by using bacteriophage λDNA and PLAU genes. The dynamic range achieved is noted as 105 ranging from 1 × 103 to 1 × 107 copies/µL and the measurement deviation is less than 5%. The detection limit is determined to be 1.4 copies/µL. The density of microchambers could be easily scaled for extensive applications and detection ranges by fabricating various MCP matrix structures. Given this high performance and a straightforward fabrication process of MCP, the device is expected to replace conventional PCR equipment for high fidelity and wide dynamic range single-molecule counting.


Asunto(s)
Técnicas Biosensibles , Técnicas Analíticas Microfluídicas , Nanotubos , Óxido de Zinc , ADN/química , ADN/genética , Reacción en Cadena de la Polimerasa
9.
AMB Express ; 11(1): 98, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-34191139

RESUMEN

The experiment was conducted to compare the growth performance, rumen fermentation, nutrient digestibility, and ruminal and fecal bacterial community between yaks and cattle-yaks. Ten male yaks (36-month-old) were used as the yak (YAK) group and 10 male cattle-yaks with similar age were selected as the cattle-yak (CAY) group. All the animals were fed same ration and the experiment lasted for 60 days. The results showed that the average daily gain and dry matter intake of CAY group were higher (P < 0.05) than those of YAK group. The ruminal concentrations of total volatile fatty acids, acetate, and butyrate were higher (P < 0.05) in CAY group than those in YAK group. However, the neutral detergent fiber and acid detergent fiber digestibility exhibited an opposite between two groups. In the rumen, the relative abundances of Prevotella 1 and Prevotellaceae UCG-001 were higher (P < 0.05) and Succiniclasticum and Butyrivibrio 2 were lower (P < 0.05) in YAK group compared to CAY group. In the feces, the unclassified Lachnospiraceae, Lachnospiraceae NK4A136 group, and Lachnospiraceae AC2044 group were significantly enriched (P < 0.05) in YAK group, whereas the Ruminococcaceae UCG-010, Ruminococcaceae UCG-013, and Succiniclasticum were significantly enriched (P < 0.05) in CAY group. Overall, under the same diet, the yaks have higher fiber utilization and cattle-yaks have higher energy utilization.

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