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1.
Sensors (Basel) ; 24(10)2024 May 08.
Article in English | MEDLINE | ID: mdl-38793847

ABSTRACT

Ensuring precise prediction of the remaining useful life (RUL) for bearings in rolling machinery is crucial for preventing sudden machine failures and optimizing equipment maintenance strategies. Since the significant interference encountered in real industrial environments and the high complexity of the machining process, accurate and robust RUL prediction of rolling bearings is of tremendous research importance. Hence, a novel RUL prediction model called CNN-VAE-MBiLSTM is proposed in this paper by integrating advantages of convolutional neural network (CNN), variational autoencoder (VAE), and multiple bi-directional long short-term memory (MBiLSTM). The proposed approach includes a CNN-VAE model and a MBiLSTM model. The CNN-VAE model performs well for automatically extracting low-dimensional features from time-frequency spectrum of multi-axis signals, which simplifies the construction of features and minimizes the subjective bias of designers. Based on these features, the MBiLSTM model achieves a commendable performance in the prediction of RUL for bearings, which independently captures sequential characteristics of features in each axis and further obtains differences among multi-axis features. The performance of the proposed approach is validated through an industrial case, and the result indicates that it exhibits a higher accuracy and a better anti-noise capacity in RUL predictions than comparable methods.

2.
Article in English | MEDLINE | ID: mdl-38083733

ABSTRACT

Research advancement has spurred the usage of electroencephalography (EEG)-based neural oscillatory rhythms as a biomarker to complement clinical rehabilitation strategies for the recovery of motor functions in stroke survivors. However, the inevitable contamination of EEG signals with artifacts from various sources limits its utilization and effectiveness. Thus, the integration of Independent Component Analysis (ICA) and Independent Component Label (ICLabel) has been widely employed to separate neural activity from artifacts. A crucial step in the ICLabel preprocessing pipeline is the artifactual ICs rejection threshold (TH) parameter, which determines the overall signal's quality. For instance, selecting a high TH will cause many ICs to be rejected, thereby leading to signal over-cleaning, and choosing a low TH may result in under-cleaning of the signal. Toward determining the optimal TH parameter, this study investigates the effect of six different TH groups (NO-TH and TH1-TH6) on EEG signals recorded from post-stroke patients who performed four distinct motor imagery (MI) tasks including wrist and grasping movements. Utilizing the EEG-beta band signal at the brain's sensorimotor cortex, the performance of the TH groups was evaluated using three notable EEG quantifiers. Overall, the obtained result shows that the considered THs will significantly alter neural oscillatory patterns. Comparing the performance of the TH-groups, TH-3 with a confidence level of 60% showed consistently stronger signal desynchronization and lateralization. The correlation result shows that most of the electrode pairs with high correlation values are replicable across all the MI tasks. It also revealed that brain activity correlates linearly with distance, and a strong correlation between electrode pairs is independent of the different brain cortices. The study outcome may facilitate adequate therapeutic intervention for stroke rehab.Clinical Relevance: This study indicated that optimal selection of the ICLabel artifactual rejection threshold is essential for EEG enhancement for adequate signal characterization. Thus, a TH-values with a confidence level between 50% - 70% would be suggested for artifactual ICs rejection in MI-EEG.


Subject(s)
Stroke , Humans , Stroke/complications , Stroke/diagnosis , Brain , Electroencephalography , Movement , Wrist
3.
Adv Healthc Mater ; 12(28): e2301370, 2023 11.
Article in English | MEDLINE | ID: mdl-37437207

ABSTRACT

Continuous oxidative stress and cellular dysfunction caused by hyperglycemia are distinguishing features of diabetic wounds. It has been a great challenge to develop a smart dressing that can accelerate diabetic wound healing through regulating abnormal microenvironments. In this study, a platelet rich plasma (PRP) loaded multifunctional hydrogel with reactive oxygen species (ROS) and glucose dual-responsive property is reported. It can be conveniently prepared with PRP, dopamine (DA) grafted alginate (Alg-DA), and 6-aminobenzo[c][1,2]oxaborol-1(3H)-ol (ABO) conjugated hyaluronic acid (HA-ABO) through ionic crosslinks, hydrogen-bond interactions, and boronate ester bonds. The hydrogel possesses injectability, moldability, tissue adhesion, self-healing, low hemolysis, and hemostasis performances. Its excellent antioxidant property can create a low oxidative stress microenvironment for other biological events. Under an oxidative stress and/or hyperglycemia state, the hydrogel can degrade at an accelerated rate to release a variety of cytokines derived from activated blood platelets. The result is a series of positive changes that are favorable for diabetic wound healing, including fast anti-inflammation, activated macrophage polarization toward M2 phenotype, promoted migration and proliferation of fibroblasts, as well as expedited angiogenesis. This work provides an efficient strategy for chronic diabetic wound management and offers an alternative for developing a new-type PRP-based bioactive wound dressing.


Subject(s)
Diabetes Mellitus , Hyperglycemia , Platelet-Rich Plasma , Humans , Hydrogels/pharmacology , Alginates , Dopamine , Anti-Bacterial Agents
4.
Int J Biol Macromol ; 247: 125820, 2023 Aug 30.
Article in English | MEDLINE | ID: mdl-37451377

ABSTRACT

The heavy metal ions contained in industrial wastewater are a great threat to human health. Exploring a adsorbent which have low-cost, green environmental friendly, high adsorption capacity, good recycle is key to solve heavy metal ions pollution. Lignin sulfonate was obtained by treating corn stover, and then modified lignin sulfonate was obtained by hydrothermal method. The porous structure makes heavy metal ions occupy more internal adsorption sites. Modified lignosulfonate adsorbent efficiency removes heavy metals in wastewater especially Cu2+ and Pb2+. The adsorption capacity of Cu2+ on modified lignosulfonate is 450.3 mg g-1, Pb2+ is 475.4 mg g-1. In addition, for 40 mg L-1 Cu2+ and Pb2+ using 0.4 g L-1, the adsorption equilibrium is only reached within 60 min. Meanwhile, the removal ratio of Pb is 83 %, Cd is 72 %, Cu is 87 %, Zn is 36 %, Mn is 25 %, Cr is 95 %, and Fe is 99 % in wastewater using 0.4 g L-1 adsorbent in 2 h. This research develops a practical adsorbent to remove heavy metals from actual wastewater.


Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Humans , Wastewater , Zea mays , Lignin , Lead , Adsorption , Water Pollutants, Chemical/chemistry , Metals, Heavy/chemistry , Kinetics , Hydrogen-Ion Concentration
5.
Comput Methods Programs Biomed ; 238: 107614, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37244233

ABSTRACT

BACKGROUND AND OBJECTIVE: Accurate and efficient segmentation of thyroid nodules on ultrasound images is critical for computer-aided nodule diagnosis and treatment. For ultrasound images, Convolutional neural networks (CNNs) and Transformers, which are widely used in natural images, cannot obtain satisfactory segmentation results, because they either cannot obtain precise boundaries or segment small objects. METHODS: To address these issues, we propose a novel Boundary-preserving assembly Transformer UNet (BPAT-UNet) for ultrasound thyroid nodule segmentation. In the proposed network, a Boundary point supervision module (BPSM), which adopts two novel self-attention pooling approaches, is designed to enhance boundary features and generate ideal boundary points through a novel method. Meanwhile, an Adaptive multi-scale feature fusion module (AMFFM) is constructed to fuse features and channel information at different scales. Finally, to fully integrate the characteristics of high-frequency local and low-frequency global, the Assembled transformer module (ATM) is placed at the bottleneck of the network. The correlation between deformable features and features-among computation is characterized by introducing them into the above two modules of AMFFM and ATM. As the design goal and eventually demonstrated, BPSM and ATM promote the proposed BPAT-UNet to further constrain boundaries, whereas AMFFM assists to detect small objects. RESULTS: Compared to other classical segmentation networks, the proposed BPAT-UNet displays superior segmentation performance in visualization results and evaluation metrics. Significant improvement of segmentation accuracy was shown on the public thyroid dataset of TN3k with Dice similarity coefficient (DSC) of 81.64% and 95th percentage of the asymmetric Hausdorff distance (HD95) of 14.06, whereas those on our private dataset were with DSC of 85.63% and HD95 of 14.53, respectively. CONCLUSIONS: This paper presents a method for thyroid ultrasound image segmentation, which achieves high accuracy and meets the clinical requirements. Code is available at https://github.com/ccjcv/BPAT-UNet.


Subject(s)
Thyroid Nodule , Humans , Thyroid Nodule/diagnostic imaging , Ultrasonography , Benchmarking , Diagnosis, Computer-Assisted , Image Processing, Computer-Assisted
6.
Materials (Basel) ; 16(7)2023 Mar 24.
Article in English | MEDLINE | ID: mdl-37048877

ABSTRACT

The hardened cement paste powder (HCP) powder, devoid of the hydration cementing property, can be regenerated and cemented into a test block with practical strength of almost 60 MPa via CO2 carbonization using appropriate means. This study established a kinetic model of CO2 curing of an HCP powder test block based on the degree of carbonization to study the carbonization reaction kinetic characteristics of the test block. The model was modified according to the characteristics of the evident temperature differences in the reaction kettle in the early, middle, and late stages of the carbonization process. The proposed model can be used to formulate and control the carbonization and cementation processes of HCP powder and can also be applied to describe the kinetics of the reaction processes of other similar systems.

7.
Front Biosci (Landmark Ed) ; 28(12): 367, 2023 12 29.
Article in English | MEDLINE | ID: mdl-38179737

ABSTRACT

BACKGROUND: Vascular endothelial dysfunction is an early phenotype of aging-related vascular dysfunction. Delaying vascular aging and preventing cardiovascular disease are major public health problems that urgently need to be solved. Scientists have studied various drugs to prevent the occurrence and progress of cardiovascular disease, but progress has been slow. Here, the antisenescence and anti-endothelial damage of canthaxanthin (CX, which is an active molecule from food) has been studied. METHODS: This study was performed by adding CX to a model of cell senescence and oxidative damage induced by hydrogen peroxide. Cellular senescence markers (e.g., p16, p21, and p53) and oxidative damage markers (e.g., reactive oxygen species, nitric oxide, malondialdehyde, superoxide dismutase) were evaluated by the enzyme-linked immunosorbent assay, laser scanning confocal microscopy, and Western blotting. RESULTS: We found that CX downregulated the expression level of senescence-associated molecules, and significantly reduced the oxidative damage of vascular endothelial cells. These observations showed that CX effectively alleviated the senescence of vascular endothelial cells. Furthermore, CX treatment reduced the expression levels of interleukin-6 (IL-6), tumor necrosis factor alpha, and IL-1ß. Finally, in vivo, CX significantly alleviated vascular senescence. CONCLUSIONS: The current study shows that CX has potential application value for treating vascular aging or endothelial cell senescence.


Subject(s)
Canthaxanthin , Cardiovascular Diseases , Mice , Animals , Canthaxanthin/pharmacology , Endothelial Cells , Aging , Cellular Senescence/genetics , Oxidative Stress , Inflammation
8.
Front Oncol ; 12: 900340, 2022.
Article in English | MEDLINE | ID: mdl-35965563

ABSTRACT

Prostate cancer diagnosis is performed under ultrasound-guided puncture for pathological cell extraction. However, determining accurate prostate location remains a challenge from two aspects: (1) prostate boundary in ultrasound images is always ambiguous; (2) the delineation of radiologists always occupies multiple pixels, leading to many disturbing points around the actual contour. We proposed a boundary structure-preserving U-Net (BSP U-Net) in this paper to achieve precise prostate contour. BSP U-Net incorporates prostate shape prior to traditional U-Net. The prior shape is built by the key point selection module, which is an active shape model-based method. Then, the module plugs into the traditional U-Net structure network to achieve prostate segmentation. The experiments were conducted on two datasets: PH2 + ISBI 2016 challenge and our private prostate ultrasound dataset. The results on PH2 + ISBI 2016 challenge achieved a Dice similarity coefficient (DSC) of 95.94% and a Jaccard coefficient (JC) of 88.58%. The results of prostate contour based on our method achieved a higher pixel accuracy of 97.05%, a mean intersection over union of 93.65%, a DSC of 92.54%, and a JC of 93.16%. The experimental results show that the proposed BSP U-Net has good performance on PH2 + ISBI 2016 challenge and prostate ultrasound image segmentation and outperforms other state-of-the-art methods.

9.
Biomed Res Int ; 2022: 6243971, 2022.
Article in English | MEDLINE | ID: mdl-35601151

ABSTRACT

Silver staining is an excellent technique for detecting proteins that are separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Protein silver staining technology has higher sensitivity and is suitable for the detection of low-concentration proteins compared to other staining techniques including the Coomassie brilliant blue detection method. The present study was conducted to enhance the detection ability of the protein staining method. Herein, we modified the recipe of silver staining, a very reproducible method, by adding AMP, PVP, Tween-80, and xylene to enhance the detection ability of protein staining. Furthermore, the particle size and potentiometer were used to detect the particle size and potential difference of the silver ions in the prepared dyeing materials, and then, the morphology, transparency, and size of the dyed silver particles in different dyeing solutions were studied using a transmission electron microscopy (TEM). The obtained results revealed that the use of 0.5% of AMP, PVP, Tween-80, and xylene improved the staining ability of protein silver staining, compared with the original method. Furthermore, 0.5% AMP, 0.5% PVP, 0.5% Tween-80 reagents significantly influenced the morphology, size, potential, and dispersion of silver ions. These results suggested a new idea for further improving the detection ability of protein silver staining.


Subject(s)
Polysorbates , Xylenes , Coloring Agents , Electrophoresis, Polyacrylamide Gel , Proteins/analysis , Rosaniline Dyes , Silver Staining , Staining and Labeling
10.
PLoS One ; 17(3): e0265845, 2022.
Article in English | MEDLINE | ID: mdl-35333895

ABSTRACT

The axial force of steel bracing is one of the essential indexes to measure the stability of the bracing system of a foundation pit. The steel bracing system of a foundation pit in Ningbo City, China was taken as the research object to guarantee the stability of the steel bracing system of the foundation pit. Besides, the change of axial force between the two steel bracing structures was analyzed to predict the axial force data of the steel bracing and perform the safety forewarning of the steel bracing system. Firstly, GM (1,1) and Verhulst models in the gray model were selected for prediction based on the characteristics of poor information and the small sample size of original monitoring data of the steel bracing. Secondly, the precision of the GM (1,1) model and Verhulst model was compared to determine a more accurate prediction method. Finally, the safety forewarning model of the confidence interval estimation method was established based on the data obtained from the prediction model and the deformation characteristics and indexes of the steel bracing. With the significance levels α = 5% and α = 2% as the demarcating points, the forewarning grades of the steel bracing system of the deep foundation pit were divided, and then the operating state of the current steel bracing system was determined. The results demonstrated that the Verhulst model had better prediction precision compared with the ordinary GM (1, 1) model. Besides, the steel bracing system was in the safe operation range, and the judgment results of the model were consistent with the actual situation of the foundation pit of the steel bracing system. Thus, the Verhulst prediction model and the confidence interval security early forewarning model could be used to judge the stability of the steel bracing system.


Subject(s)
Mechanical Phenomena , Steel , China
11.
Molecules ; 27(2)2022 Jan 06.
Article in English | MEDLINE | ID: mdl-35056650

ABSTRACT

Near-infrared (NIR) spectroscopy and characteristic variables selection methods were used to develop a quick method for the determination of cellulose, hemicellulose, and lignin contents in Sargassum horneri. Calibration models for cellulose, hemicellulose, and lignin in Sargassum horneri were established using partial least square regression methods with full variables (full-PLSR). The PLSR calibration models were established by four characteristic variables selection methods, including interval partial least square (iPLS), competitive adaptive reweighted sampling (CARS), correlation coefficient (CC), and genetic algorithm (GA). The results showed that the performance of the four calibration models, namely iPLS-PLSR, CARS-PLSR, CC-PLSR, and GA-PLSR, was better than the full-PLSR calibration model. The iPLS method was best in the performance of the models. For iPLS-PLSR, the determination coefficient (R2), root mean square error (RMSE), and residual predictive deviation (RPD) of the prediction set were as follows: 0.8955, 0.8232%, and 3.0934 for cellulose, 0.8669, 0.4697%, and 2.7406 for hemicellulose, and 0.7307, 0.7533%, and 1.9272 for lignin, respectively. These findings indicate that the NIR calibration models can be used to predict cellulose, hemicellulose, and lignin contents in Sargassum horneri quickly and accurately.


Subject(s)
Algorithms , Cellulose/analysis , Lignin/analysis , Polysaccharides/analysis , Sargassum/chemistry , Spectroscopy, Near-Infrared/methods , Calibration , Least-Squares Analysis
12.
Materials (Basel) ; 14(2)2021 Jan 13.
Article in English | MEDLINE | ID: mdl-33451148

ABSTRACT

The rolling contact fatigue of gear surfaces in a heavy loader gearbox is investigated under various working conditions using the critical plane-based multiaxial Fatemi-Socie criterion. The mechanism for residual stress to increase the fatigue initiation life is that the compressive residual stress has a negative normal component on the critical plane. Based on this mechanism, the genetic algorithm is used to search the optimum residual stress distribution that can maximize the fatigue initiation life for a wide range of working conditions. The optimum residual stress distribution is more effective in increasing the fatigue initiation life when the friction coefficient is larger than its critical value, above which the fatigue initiation moves from the subsurface to the surface. Finally, the effect on the fatigue initiation life when the residual stress distribution deviates from the optimum distribution is analyzed. A sound physical explanation for this effect is provided. This yields a useful guideline to design the residual stress distribution.

13.
Eur J Prev Cardiol ; 27(13): NP6-NP15, 2020 09.
Article in English | MEDLINE | ID: mdl-23928568

ABSTRACT

BACKGROUND: The consumption of nuts was reported to be associated with risk of hypertension and type 2 diabetes mellitus (T2DM), but the results were inconclusive. The aim of this study was to systematically examine longitudinal studies investigating nut intake in relation to risk of hypertension and T2DM. METHODS: A systematic search of the PubMed and EMBASE databases to 31 March 2013 was performed. Reference lists of retrieved articles were also screened. Summary relative risks (SRRs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Q and I2 statistics were used to examine between-study heterogeneity. RESULTS: A total of nine prospective cohort studies (three for hypertension and six for T2DM) were identified. Using random effects models, we found that based on the highest vs lowest analysis, nut consumption were inversely associated with risk of hypertension (SRR = 0.84, 95% CI: 0.76-0.93, pheterogeneity = 0.831, I2 = 0%). Dose-response analyses indicated that nut consumption at more than two servings/wk, but not ne serving/wk, had a preventative role in the hypertension. In addition, nut consumption was not associated with risk of T2DM (SRRs = 0.98, 95% CI: 0.84-1.15; pheterogeneity = 0.008, I2 = 67.7%) on the basis of the highest vs lowest analysis. This null association was also shown in the dose-response analysis. CONCLUSION: In our meta-analysis, nut consumption is found to be inversely associated with hypertension risk but is not associated with the risk of T2DM.

14.
Comput Methods Programs Biomed ; 184: 105097, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31634807

ABSTRACT

BACKGROUND AND OBJECTIVE: The prostate cancer interventions, which need an accurate prostate segmentation, are performed under ultrasound imaging guidance. However, prostate ultrasound segmentation is facing two challenges. The first is the low signal-to-noise ratio and inhomogeneity of the ultrasound image. The second is the non-standardized shape and size of the prostate. METHODS: For prostate ultrasound image segmentation, this paper proposed an accurate and efficient method of Active shape model (ASM) with Rayleigh mixture model Clustering (ASM-RMMC). Firstly, Rayleigh mixture model (RMM) is adopted for clustering the image regions which present similar speckle distributions. These content-based clustered images are then used to initialize and guide the deformation of an ASM model. RESULTS: The performance of the proposed method is assessed on 30 prostate ultrasound images using four metrics as Mean Average Distance (MAD), Dice Similarity Coefficient (DSC), False Positive Error (FPE) and False Negative Error (FNE). The proposed ASM-RMMC reaches high segmentation accuracy with 95% ± 0.81% for DSC, 1.86 ±â€¯0.02 pixels for MAD, 2.10% ± 0.36% for FPE and 2.78% ± 0.71% for FNE, respectively. Moreover, the average segmentation time is less than 8 s when treating a single prostate ultrasound image through ASM-RMMC. CONCLUSIONS: This paper presents a method for prostate ultrasound image segmentation, which achieves high accuracy with less computational complexity and meets the clinical requirements.


Subject(s)
Models, Theoretical , Prostate/diagnostic imaging , Ultrasonography , Algorithms , Cluster Analysis , Humans , Image Processing, Computer-Assisted/methods , Male , Prostatic Neoplasms/diagnostic imaging , Signal-To-Noise Ratio
15.
J Hepatol ; 69(3): 705-717, 2018 09.
Article in English | MEDLINE | ID: mdl-29705240

ABSTRACT

BACKGROUND AND AIMS: Fatty acid translocase CD36 (CD36) is a membrane protein with multiple immuno-metabolic functions. Palmitoylation has been suggested to regulate the distribution and functions of CD36, but little is known about its significance in non-alcoholic steatohepatitis (NASH). METHODS: Human liver tissue samples were obtained from patients undergoing liver biopsy for diagnostic purposes. CD36 knockout mice were injected with lentiviral vectors expressing wild-type CD36 or CD36 with mutated palmitoylation sites. Liver histology, immunofluorescence, mRNA expression profile, subcellular distributions and functions of CD36 protein were assessed. RESULTS: The localization of CD36 on the plasma membrane of hepatocytes was markedly increased in patients with NASH compared to patients with normal liver and those with simple steatosis. Increased CD36 palmitoylation and increased localization of CD36 on the plasma membrane of hepatocytes were also observed in livers of mice with NASH. Furthermore, inhibition of CD36 palmitoylation protected mice from developing NASH. The absence of palmitoylation decreased CD36 protein hydrophobicity reducing its localization on the plasma membrane as well as in lipid raft of hepatocytes. Consequently, a lack of palmitoylation decreased fatty acid uptake and CD36/Fyn/Lyn complex in HepG2 cells. Inhibition of CD36 palmitoylation not only ameliorated intracellular lipid accumulation via activation of the AMPK pathway, but also inhibited the inflammatory response through the inhibition of the JNK signaling pathway. CONCLUSIONS: Our findings demonstrate the key role of palmitoylation in regulating CD36 distributions and its functions in NASH. Inhibition of CD36 palmitoylation may represent an effective therapeutic strategy in patients with NASH. LAY SUMMARY: Fatty acid translocase CD36 (CD36) is a multifunctional membrane protein which contributes to the development of liver steatosis. In the present study, we demonstrated that the localization of CD36 on the plasma membrane of hepatocytes is increased in patients with non-alcoholic steatohepatitis. Blocking the palmitoylation of CD36 reduces CD36 distribution in hepatocyte plasma membranes and protects mice from non-alcoholic steatohepatitis. The inhibition of CD36 palmitoylation not only improved fatty acid metabolic disorders but also reduced the inflammatory response in vitro and in vivo. The present study suggests that CD36 palmitoylation is important for non-alcoholic steatohepatitis development and inhibition of CD36 palmitoylation could be used to cure non-alcoholic steatohepatitis.


Subject(s)
CD36 Antigens/metabolism , Fatty Acids, Nonesterified/metabolism , Lipid Metabolism/immunology , Lipoylation/immunology , Liver , Non-alcoholic Fatty Liver Disease , Adenosine Monophosphate/metabolism , Animals , Hep G2 Cells , Humans , Inflammation/metabolism , Liver/metabolism , Liver/pathology , MAP Kinase Signaling System , Mice , Mice, Knockout , Non-alcoholic Fatty Liver Disease/immunology , Non-alcoholic Fatty Liver Disease/metabolism
16.
Exp Ther Med ; 9(6): 2225-2228, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26136964

ABSTRACT

The aim of the present study was to observe the myocardial expression of members of the histone deacetylase (HDAC) family (HDAC2, HDAC5 and HDAC9) in rats with or without myocardial hypertrophy (MH) in the presence and absence of the angiotensin II receptor blocker valsartan. Adult male Wistar rats were randomly divided into three groups (n=6/group): Sham-operated control rats, treated with distilled water (1 ml/day) through gavage; rats with MH (established through aortic constriction), treated with distilled water (1 ml/day) through gavage; and MH + valsartan rats, treated with 20 mg/kg/day valsartan through gavage. Treatments commenced one day after surgery and continued for eight weeks. Body weight (BW), heart weight (HW) and plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels were determined, and the myocardial expression of HDAC2, HDAC5 and HDAC9 was analyzed through a reverse transcription semi-quantitative polymerase chain reaction. The BWs of the rats in the three groups were similar at baseline; however, after eight weeks the BW of the rats in the MH + valsartan group was significantly reduced compared with that of the MH rats. Furthermore, the HW/BW ratio and plasma ANP and BNP levels were increased, the myocardial HDAC2 expression was significantly upregulated and the HDAC5 and HDAC9 expression was significantly downregulated in the MH rats compared with those in the control rats; however, these changes were significantly attenuated by valsartan. Modulation of myocardial HDAC5, HDAC9 and HDAC2 expression may therefore be one of the anti-hypertrophic mechanisms of valsartan in this rat MH model.

17.
J Cell Mol Med ; 19(3): 642-50, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25656605

ABSTRACT

BACKGROUND: Phospholemman (PLM) is an important phosphorylation substrate for protein kinases A and C in the heart. Until now, the association between PLM phosphorylation status and L-type calcium channels (LTCCs) gating has not been fully understood. We investigated the kinetics of LTCCs in HEK 293T cells expressing phosphomimetic or nonphosphorylatable PLM mutants. METHODS: The LTCCs gating was measured in HEK 293T cells transfected with LTCC and wild-type (WT) PLM, phosphomimetic or nonphosphorylatable PLM mutants: 6263AA, 6869AA, AAAA, 6263DD, 6869DD or DDDD. RESULTS: WT PLM significantly slowed LTCCs activation and deactivation while enhanced voltage-dependent inactivation (VDI). PLM mutants 6869DD and DDDD significantly increased the peak of the currents. 6263DD accelerated channel activation, while 6263AA slowed it more than WT PLM. 6869DD significantly enhanced PLM-induced increase of VDI. AAAA slowed the channel activation more than 6263AA, and DDDD accelerated the channel VDI more than 6869DD. CONCLUSIONS: Our results demonstrate that phosphomimetic PLM could stimulate LTCCs and alter their dynamics, while PLM nonphosphorylatable mutant produced the opposite effects.


Subject(s)
Calcium Channels, L-Type/genetics , Membrane Proteins/genetics , Membrane Proteins/metabolism , Myocytes, Cardiac/metabolism , Phosphoproteins/genetics , Phosphoproteins/metabolism , Phosphorylation/genetics , Cell Line , HEK293 Cells , Humans , Mutation/genetics , Patch-Clamp Techniques
18.
ChemSusChem ; 8(7): 1147-50, 2015 Apr 13.
Article in English | MEDLINE | ID: mdl-25469500

ABSTRACT

As a potential solution to concerns on sustainable energy, the wide spread commercialization of fuel cell has long been hindered by limited reserves and relatively high costs of metal catalysts. 3D graphene, a carbon-only catalyst prepared by reduction of carbon monoxide with lithium oxide, is found to electrochemically catalyze carbohydrazide oxidation reaction efficiently. A prototype of a completely metal-catalyst-free anion exchange membrane fuel cell (AEMFC) with a 3D graphene anode catalyst and an N-doped CNT (N-CNT) cathode catalyst generate a peak power density of 24.9 mW cm(-2) . The average number of electrons electrochemically extracted from one carbohydrazide molecule is 4.9, indicating the existence of CN bond activation, which is a key factor contributing to high fuel utilization efficiency.


Subject(s)
Electric Power Supplies , Graphite/chemistry , Hydrazines/chemistry , Electrochemistry , Electrodes , Ion Exchange , Membranes, Artificial , Models, Molecular , Molecular Conformation
19.
J Diabetes ; 7(2): 202-12, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24893671

ABSTRACT

BACKGROUND: Inconclusive reports have been published on the consumption of nuts and the risk of hypertension and type 2 diabetes mellitus (T2DM). We performed a meta-analysis of prospective studies to assess the effects of nut consumption on hypertension and T2DM risks. METHODS: A PUBMED and EMBASE database search was performed. Summary relative risks (SRRs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Q and I2 statistics were used to examine between-study heterogeneity. RESULTS: A total of eight articles with nine prospective cohort studies (three hypertension studies and six T2DM studies) were selected. Using random effects models, we found that compared with never/rare consumers of nuts, those consuming >2 servings per week had an 8% lower risk of hypertension (SRR = 0.92, 95% CI: 0.87-0.97, P(heterogeneity) = 0.590, I2 = 0%), while consumption of nuts at one serving per week had similar risk (SRR = 0.97, 95% CI: 0.83-1.13). In addition, nuts consumption was not associated with risk of T2DM (SRRs = 0.98, 95% CI: 0.84-1.15; P(heterogeneity) = 0.008, I2 = 67.7%) on the basis of the highest versus lowest analysis. This null association was also shown in the dose-response analysis. CONCLUSION: Findings from this meta-analysis indicate that consumption of nuts (>2 servings/week) may be inversely associated with hypertension risk, but not with T2DM risk.


Subject(s)
Diabetes Mellitus, Type 2/epidemiology , Hypertension/epidemiology , Hypertension/prevention & control , Nuts , Databases, Factual , Humans , Incidence , Prognosis , Prospective Studies , Risk Reduction Behavior
20.
Invest Ophthalmol Vis Sci ; 55(10): 6722-7, 2014 Sep 25.
Article in English | MEDLINE | ID: mdl-25257056

ABSTRACT

PURPOSE: The aim of this study was to explore the possible interactions between vitelline membrane outer layer 1 homolog (VMO1) and other tear proteins and to determine the function of VMO1 in tear fluid. METHODS: Interactions between recombinant human VMO1 and several abundant tear proteins were determined by dot blot, His pull-down, immunoprecipitation, and Western blot assays, as well as by computer-assisted prediction and modeling of molecular interactions. Kirby-Bauer antibiotic testing was performed to determine whether VMO1 possesses antimicrobial activity. Tear samples were collected from dry eye patients and from healthy controls. The role of VMO1 in maintaining the stability of tear film was investigated by measurement of contact angles on Teflon, tear break-up time (TBUT) and the time-dependent reduction in tear film integrity in mice. RESULTS: Vitelline membrane outer layer 1 homolog showed an interaction with lysozyme C (LYSC) in the dot-blot, His pull-down, and immunoprecipitation assays. Vitelline membrane outer layer 1 homolog revealed no zones of growth inhibition of standard strains of Staphylococcus aureus and Escherichia coli. Tears presented smaller contact angles on Teflon surfaces after the addition of VMO1 (P<0.05). Vitelline membrane outer layer 1 homolog-treated mice showed longer TBUTs (P<0.05). Tear films from VMO1-treated mice maintained their integrity for longer periods of time than tear films from the control group, and this effect was dose-dependent. CONCLUSIONS: Vitelline membrane outer layer 1 homolog interacts with LYSC and has positive effects on the stabilization of tear film.


Subject(s)
Dry Eye Syndromes/metabolism , Egg Proteins/metabolism , Muramidase/metabolism , Tears/physiology , Animals , Blotting, Western , Disease Models, Animal , Humans , Immunoprecipitation , Mice , Mice, Inbred C57BL
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