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1.
Hum Brain Mapp ; 45(3): e26624, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38376240

RESUMO

Spinocerebellar ataxia type 3 (SCA3) is an inherited movement disorder characterized by a progressive decline in motor coordination. Despite the extensive functional connectivity (FC) alterations reported in previous SCA3 studies in the cerebellum and cerebellar-cerebral pathways, the influence of these FC disturbances on the hierarchical organization of cerebellar functional regions remains unclear. Here, we compared 35 SCA3 patients with 48 age- and sex-matched healthy controls using a combination of voxel-based morphometry and resting-state functional magnetic resonance imaging to investigate whether cerebellar hierarchical organization is altered in SCA3. Utilizing connectome gradients, we identified the gradient axis of cerebellar hierarchical organization, spanning sensorimotor to transmodal (task-unfocused) regions. Compared to healthy controls, SCA3 patients showed a compressed hierarchical organization in the cerebellum at both voxel-level (p < .05, TFCE corrected) and network-level (p < .05, FDR corrected). This pattern was observed in both intra-cerebellar and cerebellar-cerebral gradients. We observed that decreased intra-cerebellar gradient scores in bilateral Crus I/II both negatively correlated with SARA scores (left/right Crus I/II: r = -.48/-.50, p = .04/.04, FDR corrected), while increased cerebellar-cerebral gradients scores in the vermis showed a positive correlation with disease duration (r = .48, p = .04, FDR corrected). Control analyses of cerebellar gray matter atrophy revealed that gradient alterations were associated with cerebellar volume loss. Further FC analysis showed increased functional connectivity in both unimodal and transmodal areas, potentially supporting the disrupted cerebellar functional hierarchy uncovered by the gradients. Our findings provide novel evidence regarding alterations in the cerebellar functional hierarchy in SCA3.


Assuntos
Conectoma , Doença de Machado-Joseph , Humanos , Doença de Machado-Joseph/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Cerebelo/patologia , Córtex Cerebelar
2.
Artif Organs ; 48(5): 504-513, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38146899

RESUMO

BACKGROUND: A percutaneous ventricular assist device (pVAD) is an effective method to treat heart failure, but its complications, mainly hemolysis and thrombus formation, cannot be ignored. Accurate evaluation of hemolysis and thrombus formation in pVAD is essential to guide the development of pVAD and reduce the incidence of complications. METHODS: This study optimized the numerical model to predict hemolysis and thrombus formation in pVAD. The hemolysis model is based on the power law function, and the multi-component thrombus prediction model is improved by introducing the von Willebrand factor. RESULTS: The error between the numerical simulation and the hydraulic performance experiment is within 5%. The numerical results of hemolysis are in good agreement with those of in vitro experiments. Meanwhile, the thrombus location predicted by the numerical model is the same as that found in the in vivo experiment. CONCLUSION: The numerical model suggested in this study may therefore accurately assess the possible hemolytic and thrombotic dangers in pVAD, making it an effective tool to support the development of pVAD.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Trombose , Humanos , Hemólise , Coração Auxiliar/efeitos adversos , Insuficiência Cardíaca/cirurgia , Simulação por Computador , Trombose/etiologia
3.
Biomed Eng Online ; 22(1): 56, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37303051

RESUMO

Blood flow and pressure calculated using the currently available methods have shown the potential to predict the progression of pathology, guide treatment strategies and help with postoperative recovery. However, the conspicuous disadvantage of these methods might be the time-consuming nature due to the simulation of virtual interventional treatment. The purpose of this study is to propose a fast novel physics-based model, called FAST, for the prediction of blood flow and pressure. More specifically, blood flow in a vessel is discretized into a number of micro-flow elements along the centerline of the artery, so that when using the equation of viscous fluid motion, the complex blood flow in the artery is simplified into a one-dimensional (1D) steady-state flow. We demonstrate that this method can compute the fractional flow reserve (FFR) derived from coronary computed tomography angiography (CCTA). 345 patients with 402 lesions are used to evaluate the feasibility of the FAST simulation through a comparison with three-dimensional (3D) computational fluid dynamics (CFD) simulation. Invasive FFR is also introduced to validate the diagnostic performance of the FAST method as a reference standard. The performance of the FAST method is comparable with the 3D CFD method. Compared with invasive FFR, the accuracy, sensitivity and specificity of FAST is 88.6%, 83.2% and 91.3%, respectively. The AUC of FFRFAST is 0.906. This demonstrates that the FAST algorithm and 3D CFD method show high consistency in predicting steady-state blood flow and pressure. Meanwhile, the FAST method also shows the potential in detecting lesion-specific ischemia.


Assuntos
Vasos Coronários , Reserva Fracionada de Fluxo Miocárdico , Humanos , Vasos Coronários/diagnóstico por imagem , Coração , Algoritmos , Física
4.
J Thromb Thrombolysis ; 52(2): 440-453, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33387208

RESUMO

Long non-coding RNA X-inactive specific transcript (LncRNA XIST) is involved in several diseases. However, the molecular mechanism of XIST and its relation with miR-133a-3p in contrast-induced nephropathy (CIN) remained vague. Sprague-Dawley (SD) rats were assigned to Control, Sham, and CIN groups at random (n = 15 for each group). Histological examination on the kidney tissues was performed using hematoxylin and eosin (HE) and periodic acid-Schiff (PAS) staining. Mean serum creatinine (SCr) and blood urea nitrogen (BUN) contents was measured by colorimetric microplate method. Levels of inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA). The cells viability and apoptosis were respectively detected by MTT assay and flow cytometry. Target gene and potential binding sites between XIST, miR-133a-3p and NLR Family Pyrin Domain Containing 3 (NLRP3) were predicted using online databases and confirmed by dual-luciferase reporter assay. Relative mRNA and protein expressions of XIST, miR-133a-3p, NLRP3, apoptosis-associated speck-like protein (ASC) and Cleaved caspase-1 were measured with quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot as needed. In the rat CIN model, Ioversol induced kidney morphology changes, with increase on SCr and BUN contents, elevated levels of inflammatory cytokines and upregulated expressions of XIST, NLRP3, ASC and Cleaved caspase-1. Silencing XIST reversed the effects of Ioversol on cells. MiR-133a-3p could bind with XIST and target NLRP3, and downregulating miR-133a-3p reversed the effect of silencing XIST on Ioversol-treated cells. Moreover, downregulating XIST attenuated CIN injury via regulating miR-133a-3p/NLRP3 axis.


Assuntos
Nefropatias , Animais , Caspases , Proliferação de Células , Citocinas , MicroRNAs/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , RNA Longo não Codificante/genética , Ratos , Ratos Sprague-Dawley
5.
J Sep Sci ; 44(12): 2358-2370, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33835710

RESUMO

The measurement of steroid hormones provided critical information in the clinical evaluation of endocrine disorders. In this study, we developed a high-throughput solid-phase extraction method for the analysis of 26 steroids in human serum and plasma samples by liquid chromatography-tandem mass spectrometry. Chromatographic conditions and sample preparation were optimized to achieve good separation and maximum sensitivity for these analytes. Under the optimum conditions, good linearities were achieved in the quantitative range for each steroid hormone with the correlation coefficients (r) larger than 0.99. The limits of quantitation of the method were in the range from 0.0005 to 0.7901 ng/mL. The recoveries were in the range of 87.2-114.2% with intra- and interday precision lower than 9.94%. This method has already been applied to series of samples from clinical trials, and there was no significant difference between serum and ethylenediaminetetraacetic acid plasma samples.


Assuntos
Hormônios Esteroides Gonadais/sangue , Cromatografia Líquida , Humanos , Espectrometria de Massas em Tandem
6.
Biomed Chromatogr ; 35(5): e5063, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33403706

RESUMO

A method was established for the simultaneous determination of 20 kinds of bile acids in human serum employing ultraperformance liquid chromatography-tandem mass spectrometry. Chromatographic conditions and sample preparation were optimized to achieve good separation and maximum sensitivity for these analytes. The linearity, accuracy and repeatability of the development method were validated with a series of experiments. Under the optimum conditions, good linearities were achieved in the quantitative range for each bile acid with the correlation coefficients (r2 ) >0.9901. The limit of detections (signal-noise ratio 3) of the method were in a range from 0.02 to 0.57 nmol/L. The recoveries were in the range of 88.1-109.9%, RSD < 6.12%. This method was successfully applied for the determination of bile acids in a human serum sample with simple operation, high sensitivity and good accuracy, and provides a reference for the clinical determination of bile acid content.


Assuntos
Ácidos e Sais Biliares/sangue , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Confiabilidade dos Dados , Humanos , Limite de Detecção , Sensibilidade e Especificidade
7.
Eur Radiol ; 30(10): 5748-5757, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32377814

RESUMO

OBJECTIVES: This study was to evaluate the diagnostic value of liver extracellular volume (LECV) for the staging of liver fibrosis in a cynomolgus monkey model of nonalcoholic steatohepatitis (NASH). METHODS: Forty-eight cynomolgus monkeys were enrolled in this prospective study. There are 17 healthy monkeys and 31 monkeys with NASH. Ten of these monkeys were used for repeatability assessment. The remaining 38 monkeys were used to compare LECV with other indicators including pathology fibrosis score, native T1, and serum chemical indexes by Spearman, Pearson correlation test, and ROC curves. The inter-reader variability was assessed by interclass correlation. The repeatability measurement of LECV was analyzed using Bland-Altman plots and the coefficient of variation. Partial correlation analysis was performed to assess the effects of fat content and inflammation scores on the correlation between LECV/T1 and liver fibrosis score. RESULTS: This study demonstrated a good intra-reader agreement (intraclass correlation = 0.79) of LECV in all monkeys and an excellent repeatability in 10 monkeys (coefficient of variation = 2.01%). The LECV has a strong correlation with the fibrosis score (r = 0.949; p < 0.0001), low-density lipoprotein (r = 0.72; p < 0.0001), and cholesterol (r = 0.70; p < 0.0001). LECV showed high diagnostic efficacy in the diagnosis of liver fibrosis (area under the curve of ROC, 0.945~1; p < 0.001). CONCLUSIONS: LECV may serve as a noninvasive valuable biomarker for the quantification and differentiating of the non-severe liver fibrosis (stage ≤ F3). However, circulating serum markers low-density lipoprotein and cholesterol (CHO) may not serve for this purpose. KEY POINTS: • This paper demonstrated the excellent repeatability (intraclass correlation coefficient = 0.79) of LECV in monkey animal model. • LECV-MRI has a strong correlation with histopathological fibrosis score stage (r = 0.949; p < 0.0001) and shows high diagnostic efficacy in the staging of non-severe liver fibrosis (the area under ROC curve ≥ 0.945). • The new fibrosis score maps appeared to provide a better imaging tool for the spatial assessment of liver fibrosis. It may eventually facilitate the diagnosis of liver fibrosis distribution.


Assuntos
Cirrose Hepática/diagnóstico por imagem , Fígado/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Animais , Colesterol , Modelos Animais de Doenças , Inflamação/patologia , Fígado/patologia , Cirrose Hepática/patologia , Macaca fascicularis , Imageamento por Ressonância Magnética , Masculino , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/diagnóstico por imagem , Obesidade/patologia , Variações Dependentes do Observador , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes
8.
J Food Sci Technol ; 56(7): 3380-3390, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31274906

RESUMO

To better understand the effects of ultrasonic treatment in the whole freezing process (UWF) and the maximum ice crystal formation zone (UMF) on the quality of frozen dough, the textural properties of dough and the structure of gluten were investigated. The results showed that the UWF and UMF treatments improved the textural properties of frozen dough and obtain the best effect at the 60 W/L power densities. Ultrasound-assisted freezing reduced the destructive effect of disulfide bonds on dough, and led to a state of dynamic equilibrium of hydrophobic groups. UWF treatment at 80 W/L and UMF treatment at 40 W/L had positive effects prevented the secondary structure from destruction by freezing. The network of gluten treated by ultrasound-assisted freezing was more uniform and smaller than that of traditional freezing samples, which was similar to the network structure of fresh protein. According to Pearson's correlation analysis, there was a high correlation between SH, α-helix content and springiness. There was a significant positive correlation between ß-turn and G', G″, and there was a significant negative correlation between ß-turn and hardness. These results suggest that ultrasound-assisted freezing improved the process quality of dough though reducing the damage to gluten structure caused by freezing.

9.
J Food Sci Technol ; 56(1): 462-472, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30728590

RESUMO

Various non-volatile oils are currently applied in order to prevent water evaporation from exposed surface of dough during oscillatory measurements. A systemic understanding of their effectiveness in controlling water loss and ensuring accuracy of rheological measurements is necessary. In this work, three kinds of coating oils (vaseline, dimethyl silicone oil and low viscosity silicone oil) were selected to minimize water evaporation from dough of 37%, 42% and 47% water content subjected to time sweep tests under oscillatory mode. Evolution patterns of the storage modulus, loss modulus and loss factor with time were followed, and the mechanisms responsible for the response patterns were decoupled. Disparate dynamic viscoelastic responses were found for the same dough coated with different oils. Spontaneous de-structuring of dough combined with thixotropic effect contributed to the decrease of dynamic modulus and increase of the loss factor with time. Dynamic vapor sorption tests showed that water evaporation did occur for the dough even coated with non-volatile oils including vaseline. Water evaporation led to an accelerated increase in dynamic modulus with time, while had a very limited impact on loss factor. Oil invasion only played a minor role in the decrease in dynamic modulus. The measured modulus was actually a sum of the positive and negative contributions. Vaseline was observed as an effective coating oil for rheological measurements of dough, especially with high water content.

10.
J Food Sci Technol ; 56(6): 2863-2873, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31205342

RESUMO

Response surface methodology was used to analyze effects of the amounts of pregelatinized potato flour (PGPF), hydroxypropylmethylcellulose (HPMC), egg white protein (EWP), and water on the dough fermentation and physical properties of gluten-free (GF) steamed bread based on potato flour. The results showed that PGPF, HPMC, EWP, and water at the appropriate amounts improved the maximum dough height (H m), specific volume (SV) and hardness, as well as H m correlated with SV (R 2 = 0.6993) and hardness (R 2 = 0.7273). Moreover, the optimal formulation contained 4.84 g/100 g PGPF, 1.68 g/100 g HPMC, 5.87 g/100 g EWP, and 69.69 g/100 g water, potato flour basis. Furthermore, the dietary fiber, total polyphenol content, antioxidant activity, and estimated glycemic index of the steamed GF bread were, respectively, 3.17-, 1.56-, 1.44-, and 0.75-fold of those of steamed wheat bread. The optimized steamed GF bread was found to be acceptable according to the results of sensory analysis. Information collected within this study may provide further insight for optimizing the formulation of steamed GF bread based on potato flour.

11.
J Cell Physiol ; 233(7): 5255-5266, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29206299

RESUMO

Cerebral ischemic stroke (CIS) is one of the common causes of death and disability worldwide. This study aims to investigate effect of miR-137 on endothelial progenitor cells and angiogenesis in CIS by targeting NR4A2 via the Notch pathway. Brain tissues were extracted from CIS and normal mice. Immunohistochemistry was used to determine positive rate of NR4A2 expression. Serum VEGF, Ang, HGF, and IκBα levels were determined by ELISA. RT-qPCR and Western blotting were used to determine expression of related factors. Endothelial progenitor cells in CIS mice were treated and grouped into blank, NC, miR-137 mimic, miR-137 inhibitor, siRNA-NR4A2, and miR-137 inhibitor + siRNA-NR4A2 groups, and cells in normal mice into normal group. Proliferation and apoptosis were determined by MTT and flow cytometry, respectively. NR4A2 protein expression was strongly positive in CIS mice, which showed higher serum levels of VEGF, Ang, and HGF but lower IκBα than normal mice. Compared with normal group, the rest groups (endothelial progenitor cells from CIS mice) showed decreased expressions of miR-137, Hes1, Hes5, and IκBα but elevated NR4A2, Notch, Jagged1, Hey-2, VEGF, Ang, and HGF, inhibited proliferation and enhanced apoptosis. Compared with blank and NC groups, the miR-137 mimic and siRNA-NR4A2 groups exhibited increased expression of miR-137, Hes1, Hes5, and IκBα, but decreased NR4A2, Notch, Jagged1, and Hey-2, with enhanced proliferation and attenuated apoptosis. The miR-137 inhibitor group reversed the conditions. miR-137 enhances the endothelial progenitor cell proliferation and angiogenesis in CIS mice by targeting NR4A2 through the Notch signaling pathway.


Assuntos
Isquemia Encefálica/genética , MicroRNAs/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Acidente Vascular Cerebral/genética , Animais , Apoptose , Isquemia Encefálica/sangue , Isquemia Encefálica/fisiopatologia , Proliferação de Células/genética , Modelos Animais de Doenças , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Regulação da Expressão Gênica , Humanos , Camundongos , Neovascularização Patológica/sangue , Neovascularização Patológica/genética , Neovascularização Patológica/fisiopatologia , Receptores Notch/genética , Transdução de Sinais , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/fisiopatologia
12.
Int J Food Sci Nutr ; 68(2): 167-178, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27608859

RESUMO

We investigated the nutritional quality of steamed and baked breads containing 35% potato flour from four potato cultivars. Compared with traditional wheat varieties, potato-wheat steamed and baked breads contained higher dietary fiber (1.87-fold), K (2.68-fold), vitamin C (28.56-fold), and total polyphenol (1.90-fold) contents and greater antioxidant activity (1.23-fold). Moreover, the estimated glycemic index of potato-wheat breads ranged from 61.20 (Hongmei-wheat baked bread) to 67.36 (Atlantic-wheat steamed bread), which was lower than that of wheat steamed bread (70.22) and baked bread (70.62). In terms of nutritional value, Hongmei was the optimum cultivar, followed by Blue Congo, Shepody, and Atlantic. For the same cultivar, the nutritional value of steamed bread was higher than that of baked bread. In conclusion, potato flour is a potential wheat flour supplement that improves the nutritional and functional properties of breads.


Assuntos
Pão/análise , Farinha , Manipulação de Alimentos , Valor Nutritivo , Solanum tuberosum , Triticum , Aminoácidos/análise , Antioxidantes/análise , Fibras na Dieta/análise , Digestão , Índice Glicêmico , Modelos Lineares , Polifenóis/análise , Oligoelementos/análise , Vitaminas/análise
13.
J Food Sci Technol ; 54(6): 1597-1607, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28559619

RESUMO

The aim of study was to investigate the effect of hydroxylpropylmethylcellulose (HPMC), arabic gum (AG), konjac glucomannan (KG) and apple pectin (AP) at 2% (w/w, potato-wheat flour basis) on the potato-wheat dough (the mass ratio was 1:1) rheological, fermentation and bread making properties. The tan δ of potato-wheat dough was significantly increased upon addition of adding HPMC which was close to wheat dough (0.531). Moreover, dough height during fermentation process was significantly improved on addition of hydrocolloids, with the order of HPMC (23.1 mm) > AP (19.3 mm) > AG (18.6 mm) > KG (13.6 mm). Protein bands of potato-wheat dough were pale in the presence of hydrocolloids, suggesting the formation of higher molecular weight aggregates formed between proteins-hydrocolloids or proteins-proteins after fermentation process. Furthermore, HPMC significantly increased specific volume (from 1.45 to 2.22 ml/g), and hydrocolloids restricted the retrogradation of starch in potato-wheat breads.

14.
J Sep Sci ; 38(22): 3928-3935, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26450357

RESUMO

A porous carbon designated as MOF-5-C was prepared by directly carbonizing a metal-organic framework (MOF-5). The morphology and microstructure of MOF-5-C were characterized by scanning electron microscopy, N2 adsorption, and powder X-ray diffraction. The MOF-5-C retained the original porous structures of MOF-5, and showed a high Brunauer-Emmett-Teller surface area (1808 m2 g-1 ) and large pore volume (3.05 cm3 g-1 ). To evaluate its adsorption performance, the MOF-5-C was used as an adsorbent for the solid-phase extraction of four phthalate esters from bottled water, peach juice, and soft drink samples followed by high-performance liquid chromatographic analysis. Several parameters that could affect the extraction efficiencies were investigated. Under the optimum conditions, a good linearity was achieved in the concentration range of 0.1-50.0 ng mL-1 for bottled water sample and 0.2-50.0 ng mL-1 for peach juice and soft drink samples. The limits of detection of the method (S/N = 3) were 0.02 ng mL-1 for bottled water sample, and 0.04-0.05 ng mL-1 for peach juice and soft drink samples. The results indicated that the MOF-5-C exhibited an excellent adsorption capability for trace levels of phthalate esters, and it could be a promising adsorbent for the preconcentration of other organic compounds.

15.
Biochem Biophys Res Commun ; 455(3-4): 234-40, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25449276

RESUMO

Intestinal endotoxemia-induced liver injury is a common clinical disease which leads to liver failure and death. Wortmannin, an inhibitor of phosphatidylinositol 3-kinase, could be used for suppressing autophagy in vitro and in vivo. Autophagy is an evolutionarily conserved and lysosome dependent protein degradation pathway, which participates in various physiological and pathological processes. The present study aims to explore the effect of pretreatment with wortmannin on acute liver injury and the autophagy in acute liver injury. We demonstrated that wortmannin could downregulate the expression of phosphorylated extracellular regulated protein kinase and p65, decrease the production and release of hepatic inflammatory cytokines, and then reduce hepatocytes apoptosis and necrosis. More importantly, we found that autophagy was induced to increase in LPS/D-GalN-induced acute liver injury, and pretreatment with wortmannin could effectively inhibit increased autophagy in acute liver injury. In conclusion, these results indicate that wortmannin plays a protective role in LPS/D-GalN induced hepatocytotoxity maybe by inhibiting autophagy and could be acted as a target for the treatment of acute liver injury.


Assuntos
Androstadienos/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Galactosamina/efeitos adversos , Lipopolissacarídeos/efeitos adversos , Falência Hepática Aguda/tratamento farmacológico , Alanina Transaminase/metabolismo , Androstadienos/uso terapêutico , Animais , Apoptose , Aspartato Aminotransferases/metabolismo , Autofagia , Citocinas/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Inflamação , Falência Hepática Aguda/induzido quimicamente , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Necrose , Inibidores de Fosfoinositídeo-3 Quinase , Wortmanina
16.
Int J Biol Macromol ; 273(Pt 2): 133196, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38885865

RESUMO

Gum arabic finds extensive application and typically undergoes sterilization prior to utilization in the food industry. This study explored the impact of steam sterilization temperature and duration on the physicochemical and emulsification characteristics of gum arabic, accompanied by proposed mechanisms elucidating observed effects. The results showed that when gum arabic was treated with high temperature sterilization (110 °C âˆ¼ 140 °C), the emulsion prepared turned unstable. The interfacial tension decreased from 8.26 mN/m to 6.77 mN/m after sterilization, while the elastic modulus decreased from 23.65 mN/m to 16.16 mN/m. Moreover, the circular dichroic chromatographic results indicated that the arabinogalactan protein (AGP) structure of gum arabic was more relaxed after high temperature treatment with ß-sheets content decreased from 36.2 % to 29.8 % and random coil content increased from 41.3 % to 51.8 %. Quartz crystal microbalance with dissipation (QCM-D) results demonstrated that emulsion surface film thickness and toughness decreased after sterilization treatment of gum arabic. The study indicates that high temperature sterilization may change protein structure in gum arabic and reduce the stability of prepared emulsions.


Assuntos
Emulsões , Goma Arábica , Vapor , Goma Arábica/química , Emulsões/química , Fenômenos Químicos , Proteínas de Plantas/química , Temperatura , Mucoproteínas/química , Esterilização/métodos , Tensão Superficial
17.
Int J Biol Macromol ; 270(Pt 1): 132421, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38759854

RESUMO

This study examines the effects of flaxseed gum (FG) on the aggregate structure, pasting and rheological properties of waxy rice starch (WRS). Results display an increase in the ordered molecular structure (R1047/1024), relative crystallinity (RC), compactness (α), and microphase heterogeneity (ε, density degree of nanoaggregates, from 3.52 to 4.23) for WRS-FG complexes. These suggested FG facilitated the development of more organized molecular and crystalline structures of WRS, accompanied by the formation of ordered nanoaggregates with higher density (i.e., nano-aggregation structure). Also, FG addition resulted in the formation of enhanced gel network structure characterized by thicker layer walls and more uniform pores. These structural transformations contributed to a rise in gelatinization temperature (To, from 56.90 °C to 62.10 °C) and enthalpy (ΔH), as well as alterations in paste viscosities (PV, from 1285.00 mPa·s to 1734.00 mPa·s), and the rigidity of network structure (e.g., decreased loss tangent). These results indicate that FG could effectively regulate the techno-functional properties of WRS by rationally controlling the starch intrinsic structures of starch. And this study may improve the pasting and gelling properties of starch, thus driving the development of high-quality starchy foods and prolonging their shelf life, especially for glutinous rice flour products.


Assuntos
Linho , Oryza , Reologia , Amido , Oryza/química , Amido/química , Linho/química , Gomas Vegetais/química , Temperatura , Viscosidade
18.
Heliyon ; 10(1): e22742, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38192835

RESUMO

Background: Continuous light exposure increases sympathetic excitation in rats, leading to hypertension, left ventricular hypertrophy, and fibrosis. This study was aimed to investigate whether continuous light exposure causes destabilization of vital signs and gut microbiota (GM) in Sprague Dawley (SD) rats and whether clonidine hydrochloride (CH), a central sympathetic depressant drug, could prevent these changes. Methods: Eight-week-old male SD rats were divided into three groups with different interventions for 14 weeks: control group (CG), 2-mL pure water gavaged daily while on a normal 12-h light/dark cycle; continuous illumination group (CI), 2-mL pure water gavaged daily while receiving continuous exposure to light (300 lx); and drug administration group (DA), CH (10 µg/kg) gavaged daily while receiving continuous exposure to light (300 lx). Results: The results showed that blood pressure, heart rate, and body weight were significantly higher in the CI group than in the CG and DA groups (P < 0.05). Moreover, the Shannon index was higher in the DA group than in the CI group (P = 0.012). The beta diversity index in the CG group was significantly higher in the CI group (P = 0.039). The pairwise comparison results of the linear discriminant analysis effect size showed that Oscillospirales were enriched in the DA group, whereas the Prevotellaceae lineage (family level) > Prevotella (genus level) > Prevotellaceae_bacterium (species level) were enriched in the CI group. The Muribaculaceae family was more abundant in the CG group than in the CI group. Conclusion: Sympathetic nerve inhibition restored the abnormal vital signs and GM changes under continuous light exposure.

19.
Int J Biol Macromol ; 267(Pt 2): 131315, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569985

RESUMO

Understanding the hierarchical structure and physicochemical properties of starch isolated from fermented dough with different times (0-120 min) is valuable for improving the quality of fermented dough-based products. The results indicate that fermentation disrupted the starch granule surface and decreased the average particle size from 19.72 µm to 18.45 µm. Short-term fermentation (< 60 min) disrupted the crystalline, lamellar, short-range ordered molecular and helical structures of starch, while long-term fermentation (60-120 min) elevated the ordered degree of these structures. For example, relative crystallinity and double helix contents increased from 23.7 % to 26.8 % and 34.4 % to 37.2 %, respectively. During short-term fermentation, the structural amorphization facilitated interactions between starch molecular chains and water molecules, which increased the peak viscosity from 275.4 to 320.6 mPa·s and the swelling power from 7.99 to 8.52 g/g. In contrast, starches extracted from long-term fermented dough displayed the opposite results. Interestingly, the hardness and springiness of starch gels gradually decreased as fermentation time increased. These findings extend our understanding of the starch structure-property relationship during varied fermentation stages, potentially benefiting the production of better-fermented foods.


Assuntos
Fermentação , Amido , Amido/química , Viscosidade , Fenômenos Químicos , Farinha/análise , Tamanho da Partícula , Pão/análise
20.
J Affect Disord ; 354: 500-508, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38484883

RESUMO

BACKGROUND: The dynamic and hierarchical nature of the functional brain network. The neural dynamical systems tend to converge to multiple attractors (stable fixed points or dynamical states) in long run. Little is known about how the changes in this brain dynamic "long-term" behavior of the connectivity flow of brain network in generalized anxiety disorder (GAD). METHODS: This study recruited 92 patients with GAD and 77 healthy controls (HC). We applied a reachable probability approach combining a Non-homogeneous Markov model with transition probability to quantify all possible connectivity flows and the hierarchical structure of brain functional systems at the dynamic level and the stationary probability vector (10-step transition probabilities) to describe the steady state of the system in the long run. A random forest algorithm was conducted to predict the severity of anxiety. RESULTS: The dynamic functional patterns in distributed brain networks had larger possibility to converge in bilateral thalamus, posterior cingulate cortex (PCC), right superior occipital gyrus (SOG) and smaller possibility to converge in bilateral superior temporal gyrus (STG) and right parahippocampal gyrus (PHG) in patients with GAD compared to HC. The abnormal transition probability pattern could predict anxiety severity in patients with GAD. LIMITATIONS: Small samples and subjects taking medications may have influenced our results. Future studies are expected to rule out the potential confounding effects. CONCLUSION: Our results have revealed abnormal dynamic neural communication and integration in emotion regulation in patients with GAD, which give new insights to understand the dynamics of brain function of patients with GAD.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Encéfalo/diagnóstico por imagem , Transtornos de Ansiedade/psicologia , Mapeamento Encefálico/métodos , Lobo Temporal
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