Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
J Dairy Sci ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38825132

RESUMO

Understanding consumers' sensory preferences for dairy products is essential. This study employed sensory analysis and instrumental techniques to analyze the flavor of pasteurized milk and ultra-high temperature (UHT) milk. There were 6 milk samples with similar fat content (4.0-4.6 g/100mL) and protein content (3.2-3.8 g/100mL). Sensory data from consumer tests was collected using CATA (n = 100) and 9-point hedonic preferences. Research showed that Chinese consumers could distinguish the flavor of the 2 types of milk, and UHT milk showed a higher preference score, which may be due to the more pronounced milky flavor and sweet taste of UHT milk. A total of 48 aroma-active compounds were sniffed through GC × GC-O-TOF-MS, among which 11 were determined as key aroma-active compounds. Correlation analysis showed that milky odor, sweetness, and aftertaste-milky were positively correlated with γ-dodecalactone and γ-nonanolactone. Cooked and oxidized taste were positively correlated with 1-octen-3-ol and E-2-octenal. This study is important for developing Chinese dairy products and exporting dairy products to China by multinational companies.

2.
Food Funct ; 15(8): 4614-4626, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38590249

RESUMO

The role of vitamin D (VD) in non-alcoholic fatty liver disease (NAFLD) remains controversial, possibly due to the differential effects of various forms of VD. In our study, Sod1 gene knockout (SKO) mice were utilized as lean NAFLD models, which were administered 15 000 IU VD3 per kg diet, or intraperitoneally injected with the active VD analog calcipotriol for 12 weeks. We found that VD3 exacerbated hepatic steatosis in SKO mice, with an increase in the levels of Cd36, Fatp2, Dgat2, and CEBPA. However, calcipotriol exerted no significant effect on hepatic steatosis. Calcipotriol inhibited the expression of Il-1a, Il-1b, Il-6, Adgre1, and TNF, with a reduction of NFκB phosphorylation in SKO mice. No effect was observed by either VD3 or calcipotriol on hepatocyte injury and hepatic fibrosis. Co-immunofluorescence stains of CD68, a liver macrophage marker, and VDR showed that calcipotriol reduced CD68 positive cells, and increased the colocalization of VDR with CD68. However, VD3 elevated hepatocyte VDR expression, with no substantial effect on the colocalization of VDR with CD68. Finally, we found that VD3 increased the levels of serum 25(OH)D3 and 24,25(OH)2D3, whereas calcipotriol decreased both. Both VD3 and calcipotriol did not disturb serum calcium and phosphate levels. In summary, our study found that VD3 accentuated hepatic steatosis, while calcipotriol diminished inflammation levels in SKO mice, and the difference might stem from their distinct cellular selectivity in activating VDR. This study provides a reference for the application of VD in the treatment of lean NAFLD.


Assuntos
Calcitriol , Calcitriol/análogos & derivados , Colecalciferol , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Calcitriol/farmacologia , Camundongos , Colecalciferol/farmacologia , Masculino , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Fígado/metabolismo , Fígado/efeitos dos fármacos , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Inflamação/tratamento farmacológico , Camundongos Endogâmicos C57BL , Humanos , Modelos Animais de Doenças
3.
Magn Reson Imaging ; 109: 108-119, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38492787

RESUMO

Magnetic resonance imaging (MRI) is non-invasive and crucial for clinical diagnosis, but it has long acquisition time and aliasing artifacts. Accelerated imaging techniques can effectively reduce the scanning time of MRI, thereby decreasing the anxiety and discomfort of patients. Vision Transformer (ViT) based methods have greatly improved MRI image reconstruction, but their computational complexity and memory requirements for the self-attention mechanism grow quadratically with image resolution, which limits their use for high resolution images. In addition, the current generative adversarial networks in MRI reconstruction are difficult to train stably. To address these problems, we propose a Local Vision Transformer (LVT) based adversarial Diffusion model (Diff-GAN) for accelerating MRI reconstruction. We employ a generative adversarial network (GAN) as the reverse diffusion model to enable large diffusion steps. In the forward diffusion module, we use a diffusion process to generate Gaussian mixture distribution noise, which mitigates the gradient vanishing issue in GAN training. This network leverages the LVT module with the local self-attention, which can capture high-quality local features and detailed information. We evaluate our method on four datasets: IXI, MICCAI 2013, MRNet and FastMRI, and demonstrate that Diff-GAN can outperform several state-of-the-art GAN-based methods for MRI reconstruction.


Assuntos
Ansiedade , Artefatos , Humanos , Difusão , Fontes de Energia Elétrica , Imageamento por Ressonância Magnética , Processamento de Imagem Assistida por Computador
4.
Phys Med Biol ; 69(8)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38479022

RESUMO

Objective.Multi-contrast magnetic resonance imaging (MC MRI) can obtain more comprehensive anatomical information of the same scanning object but requires a longer acquisition time than single-contrast MRI. To accelerate MC MRI speed, recent studies only collect partial k-space data of one modality (target contrast) to reconstruct the remaining non-sampled measurements using a deep learning-based model with the assistance of another fully sampled modality (reference contrast). However, MC MRI reconstruction mainly performs the image domain reconstruction with conventional CNN-based structures by full supervision. It ignores the prior information from reference contrast images in other sparse domains and requires fully sampled target contrast data. In addition, because of the limited receptive field, conventional CNN-based networks are difficult to build a high-quality non-local dependency.Approach.In the paper, we propose an Image-Wavelet domain ConvNeXt-based network (IWNeXt) for self-supervised MC MRI reconstruction. Firstly, INeXt and WNeXt based on ConvNeXt reconstruct undersampled target contrast data in the image domain and refine the initial reconstructed result in the wavelet domain respectively. To generate more tissue details in the refinement stage, reference contrast wavelet sub-bands are used as additional supplementary information for wavelet domain reconstruction. Then we design a novel attention ConvNeXt block for feature extraction, which can capture the non-local information of the MC image. Finally, the cross-domain consistency loss is designed for self-supervised learning. Especially, the frequency domain consistency loss deduces the non-sampled data, while the image and wavelet domain consistency loss retain more high-frequency information in the final reconstruction.Main results.Numerous experiments are conducted on the HCP dataset and the M4Raw dataset with different sampling trajectories. Compared with DuDoRNet, our model improves by 1.651 dB in the peak signal-to-noise ratio.Significance.IWNeXt is a potential cross-domain method that can enhance the accuracy of MC MRI reconstruction and reduce reliance on fully sampled target contrast images.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Processamento de Imagem Assistida por Computador/métodos , Tempo , Imageamento por Ressonância Magnética/métodos , Razão Sinal-Ruído
5.
Comput Biol Med ; 167: 107619, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37925909

RESUMO

Reconstruction methods based on deep learning have greatly shortened the data acquisition time of magnetic resonance imaging (MRI). However, these methods typically utilize massive fully sampled data for supervised training, restricting their application in certain clinical scenarios and posing challenges to the reconstruction effect when high-quality MR images are unavailable. Recently, self-supervised methods have been developed that only undersampled MRI images participate in the network training. Nevertheless, due to the lack of complete referable MR image data, self-supervised reconstruction is prone to produce incorrect structure contents, such as unnatural texture details and over-smoothed tissue sites. To solve this problem, we propose a self-supervised Deep Contrastive Siamese Network (DC-SiamNet) for fast MR imaging. First, DC-SiamNet performs the reconstruction with a Siamese unrolled structure and obtains visual representations in different iterative phases. Particularly, an attention-weighted average pooling module is employed at the bottleneck layer of the U-shape regularization unit, which can effectively aggregate valuable local information of the underlying feature map in the generated representation vector. Then, a novel hybrid loss function is designed to drive the self-supervised reconstruction and contrastive learning simultaneously by forcing the output consistency across different branches in the frequency domain, the image domain, and the latent space. The proposed method is extensively evaluated with different sampling patterns on the IXI brain dataset and the MRINet knee dataset. Experimental results show that DC-SiamNet can achieve 0.93 in structural similarity and 33.984 dB in peak signal-to-noise ratio on the IXI brain dataset under 8x acceleration. It has better reconstruction accuracy than other methods, and the performance is close to the corresponding model trained with full supervision, especially when the sampling rate is low. In addition, generalization experiments verify that our method has a strong cross-domain reconstruction ability for different contrast brain images.


Assuntos
Aceleração , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Articulação do Joelho , Razão Sinal-Ruído , Processamento de Imagem Assistida por Computador
6.
Int J Obes (Lond) ; 44(5): 1052-1061, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32203112

RESUMO

OBJECTIVE: The orphan nuclear receptor Nur77 is an important factor regulating metabolism. Nur77 knockout mice become obese with age, but the cause of obesity in these mice has not been fully ascertained. We attempted to explain the cause of obesity in Nur77 knockout mice from the perspective of the gut microbiota and to investigate the inhibitory effect of calcipotriol combined with BRD9 inhibitor (iBRD9) on obesity. METHODS: Eight-week-old wild-type mice and Nur77 knockout C57BL/6J mice were treated with calcipotriol combined with iBRD9 for 12 weeks. Mouse feces were collected and the gut microbiota was assessed by analyzing 16S rRNA gene sequences. The bacterial abundance difference was analyzed, and the intestinal mucosal tight junction protein, antimicrobial peptide, and inflammatory cytokine mRNA levels of the colon and serum LPS and inflammatory cytokine levels were measured. RESULTS: Calcipotriol combined with iBRD9 treatment reduced the body weight and body fat percentage in Nur77 knockout mice. In the gut microbiota of Nur77 knockout mice, the relative abundances of Lachnospiraceae and Prevotellaceae decreased, and Rikenellaceae increased; while Rikenellaceae decreased after treatment (p < 0.05). Correspondingly, the mRNA levels of intestinal mucosal tight junction proteins (occludin (Ocln), claudin3 (Cldn3)) in the colons of Nur77 knockout mice were significantly decreased, and they increased significantly after treatment (p < 0.001). The mRNA levels of inflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß)) were significantly increased in Nur77 knockout mice, and TNF-α and IL-6 levels were significantly decreased after treatment (p < 0.05, <0.01, or <0.001). The levels of serum LPS, TNF-α, and IL-1ß in Nur77 knockout mice were significantly increased (p < 0.05). Serum LPS, TNF-α, and IL-6 levels were significantly decreased after treatment (p < 0.05 or <0.01). CONCLUSIONS: Calcipotriol combined with iBRD9 can regulate the gut microbiota, improve intestinal mucosal barrier function, reduce LPS absorption into the blood, and alleviate obesity in Nur77 knockout mice.


Assuntos
Calcitriol/análogos & derivados , Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Obesidade/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Animais , Calcitriol/farmacologia , Citocinas/metabolismo , Mucosa Intestinal/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética
7.
J Cachexia Sarcopenia Muscle ; 11(3): 678-689, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32020783

RESUMO

OBJECTIVE: Sarcopenia in older adults is closely related to vitamin D deficiency and reduced levels of physical activity, but little has been reported on the interaction between physical activity and the positive effects of vitamin D. The purpose of this study was to explore the interactive effect of vitamin D and physical activity on muscle mass and function through animal experiments and population surveys. METHODS: Male 4-week-old C57BL/6J mice were fed different purified diets: a vitamin D-deficient diet (with increased calcium and phosphorus to prevent the effects of abnormal mineral levels on muscle) or a 1,25-dihydroxyvitamin D3 (1,25D)-supplemented diet. After 24 weeks on the assigned diets, the mice were immobilized. The level of skeletal muscle atrophy in the mice was determined by grip strength, gastrocnemius (GA) muscle mass and muscle fiber cross-sectional area (CSA); additionally, the protein expression levels of FOXO3a and the E3 ubiquitin ligases MuRF1 and MAFbx were detected. A cross-sectional study included data from 4139 older adults (64.9% women, 67.9 ± 6.7 years) as part of a survey in Shenyang, Northeast China. The associations of serum 25(OH)D3 and physical activity with timed up and go test (TUG) performance, handgrip strength, calf circumference, and body muscle mass were assessed by a linear regression analysis that was adjusted for covariates. RESULTS: In activity-limited mice, vitamin D deficiency accelerated the decrease in GA muscle weight, muscle fiber CSA, and grip strength and increased the protein expression of MuRF1, MAFbx, and FOXO3a (all P < 0.05). In addition, 1,25D supplementation may inhibit the grip-strength reduction induced by limited activity (P = 0.069). Serum 25(OH)D3 and physical activity were linearly related to TUG time (P < 0.001) and handgrip strength (P < 0.05) after adjustment for sex, age, body mass index (BMI), education level, smoking status, and serum calcium level. Serum 25(OH)D3 and physical activity had interactive effects on TUG (P < 0.001) and handgrip strength (P < 0.05) but not calf circumference or body muscle mass in older adults. CONCLUSIONS: The effect of vitamin D on muscle strength and physical performance depends on physical activity level in the elderly. It is recommended that older adults strive to avoid both physical inactivity and vitamin D deficiency. Because physical inactivity and vitamin D deficiency may exacerbate muscle atrophy, the biological mechanism may involve synergistic effects of vitamin D and physical activity on the promotion of muscle protein ubiquitination and degradation.


Assuntos
Sarcopenia/tratamento farmacológico , Deficiência de Vitamina D/complicações , Vitamina D/uso terapêutico , Animais , Humanos , Masculino , Camundongos , Desempenho Físico Funcional , Vitamina D/sangue , Vitamina D/farmacologia
8.
Clin Interv Aging ; 14: 1065-1073, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354250

RESUMO

Background and objective: Oxidative stress has been demonstrated to be a mechanism that leads to bone mass reduction, and according to many studies, serum uric acid (UA) is a strong endogenous antioxidant that can protect bone mineral density (BMD). To date, there have been no large-scale, cross-sectional studies based on the population in northeast China to assess the relationship between serum UA and BMD. Therefore, we examined the association between serum UA and BMD among a Chinese population older than 60 years old in northeast China. Methods: This research was a cross-sectional study of 3465 Chinese individuals over 60 years old in nine communities from the city of Shenyang, which is the capital of northeast China's Liaoning Province. Participants were stratified into three groups by serum UA or BMD levels, and then Pearson's correlation analysis and multiple regression analysis were used to study the relationship between serum UA and BMD. Results: We found that participants with higher serum UA levels had significantly greater BMD and T-values compared to those of participants with lower serum UA levels. After adjusting for confounding factors, Pearson's correlation analysis and multiple regression analysis showed that higher serum UA levels remained associated with higher BMD levels (P<0.05). In different models, the prevalence of osteoporosis (OP) among participants with higher serum UA levels was reduced by 23% to 26% (P<0.05) compared to that in individuals with lower serum UA levels. In addition, serum UA levels were negatively correlated with estimated glomerular filtration rate (eGFR) and positively correlated with 25-hydroxy vitamin D3 [25-(OH)D3] (P<0.05). Conclusion: We concluded that higher serum UA levels are associated with greater BMD, and serum UA might have a protective effect on bone metabolism due to its antioxidant properties.


Assuntos
Densidade Óssea/fisiologia , Osteoporose/epidemiologia , Ácido Úrico/sangue , Idoso , China/epidemiologia , Colecalciferol/sangue , Estudos Transversais , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Análise de Regressão , Fatores Socioeconômicos
9.
Med Sci Monit ; 25: 643-655, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30668558

RESUMO

BACKGROUND In recent years, many studies on vitamin D have been published. We combed these data for hot spot analyses and predicted future research topic trends. MATERIAL AND METHODS Articles (4625) concerning vitamin D published in the past 3 years were selected as a study sample. Bibliographic Items Co-occurrence Matrix Builder (BICOMB) software was used to screen high-frequency Medical Subject Headings (MeSH) terms and construct a MeSH terms-source article matrix and MeSH terms co-occurrence matrix. Then, Graphical Clustering Toolkit (gCLUTO) software was employed to analyze the matrix by double-clustering and visual analysis to detect the trends on the subject. RESULTS Ninety high-frequency major MeSH terms were obtained from 4625 articles and divided into 5 clusters, and we generated a visualized matrix and a mountain map. Strategic coordinates were established by the co-occurrence matrix of the MeSH terms based on the above classification, and the 5 clusters described above were further divided into 7 topics. We classified the vitamin D-related diseases into 12 categories and analyzed their distribution. CONCLUSIONS The analysis of strategic coordinates revealed that the epidemiological study of vitamin D deficiency and vitamin D-related diseases is a hot research topic. The use of vitamin D in the prevention and treatment of some diseases, especially diabetes, was found to have a significant potential future research value.


Assuntos
Pesquisa/tendências , Vitamina D/metabolismo , Bibliometria , Análise por Conglomerados , Humanos , Medical Subject Headings , Publicações , Software , Deficiência de Vitamina D , Vitaminas
10.
J Diabetes Investig ; 10(2): 446-457, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29923322

RESUMO

AIMS/INTRODUCTION: In the present meta-analysis, we aimed to determine the effects of sodium-glucose cotransporter 2 inhibitor (SGLT-2i) in addition to insulin therapy on cardiovascular risk factors in type 2 diabetes patients. MATERIALS AND METHODS: Randomized controlled trials were identified by searching the PubMed, Embase and Cochrane Library databases published before September 2017. The intervention group received SGLT-2i as add-on treatment to insulin therapy, and the control group received placebos in addition to insulin. We assessed pooled data, including weighted mean differences and 95% confidence intervals (CIs) using a random-effects model. RESULTS: A total of 10 randomized controlled trials (n = 5,159) were eligible. The weighted mean differences for systolic blood pressure and diastolic blood pressure were -3.17 mmHg (95% CI -4.53, -1.80, I2 = 0%) and -1.60 mmHg (95% CI -2.52, -0.69, I2 = 0%) in the intervention groups. Glycosylated hemoglobin, fasting plasma glucose, postprandial glucose and daily insulin were also lower in the intervention groups, with relative weighted mean differences of -0.49% (95% CI -0.71, -0.28%, I2 = 92%), -1.10 mmol/L (95% CI -1.69, -0.51 mmol/L, I2 = 84%), -3.63 mmol/L (95% CI -4.36, -2.89, I2 = 0%) and -5.42 IU/day (95% CI -8.12, -2.72, I2 = 93%). The transformations of uric acid and bodyweight were -26.16 µmol/L (95% CI -42.14, -10.17, I2 = 80%) and -2.13 kg (95% CI -2.66, -1.60, I2 = 83%). The relative risk of hypoglycemia was 1.09 (95% CI 1.02, 1.17, P < 0.01). The relative risks of urinary tract and genital infection were 1.29 (95% CI 1.03, 1.62, P = 0.03) and 5.25 (95% CI 3.55, 7.74, P < 0.01). CONCLUSIONS: The results showed that in the intervention group, greater reductions were achieved for blood pressure, glucose control, uric acid and bodyweight. This treatment regimen might therefore provide beneficial effects on the occurrence and development of cardiovascular events.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , China/epidemiologia , Quimioterapia Combinada , Humanos , Incidência , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA