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1.
Microsyst Nanoeng ; 9: 156, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38125202

RESUMO

Pressure sensors play a vital role in aerospace, automotive, medical, and consumer electronics. Although microelectromechanical system (MEMS)-based pressure sensors have been widely used for decades, new trends in pressure sensors, including higher sensitivity, higher accuracy, better multifunctionality, smaller chip size, and smaller package size, have recently emerged. The demand for performance upgradation has led to breakthroughs in sensor materials, design, fabrication, and packaging methods, which have emerged frequently in recent decades. This paper reviews common new trends in MEMS pressure sensors, including minute differential pressure sensors (MDPSs), resonant pressure sensors (RPSs), integrated pressure sensors, miniaturized pressure chips, and leadless pressure sensors. To realize an extremely sensitive MDPS with broad application potential, including in medical ventilators and fire residual pressure monitors, the "beam-membrane-island" sensor design exhibits the best performance of 66 µV/V/kPa with a natural frequency of 11.3 kHz. In high-accuracy applications, silicon and quartz RPS are analyzed, and both materials show ±0.01%FS accuracy with respect to varying temperature coefficient of frequency (TCF) control methods. To improve MEMS sensor integration, different integrated "pressure + x" sensor designs and fabrication methods are compared. In this realm, the intercoupling effect still requires further investigation. Typical fabrication methods for microsized pressure sensor chips are also reviewed. To date, the chip thickness size can be controlled to be <0.1 mm, which is advantageous for implant sensors. Furthermore, a leadless pressure sensor was analyzed, offering an extremely small package size and harsh environmental compatibility. This review is structured as follows. The background of pressure sensors is first presented. Then, an in-depth introduction to MEMS pressure sensors based on different application scenarios is provided. Additionally, their respective characteristics and significant advancements are analyzed and summarized. Finally, development trends of MEMS pressure sensors in different fields are analyzed.

2.
Ultrason Sonochem ; 97: 106462, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37285633

RESUMO

In this study, the ultrasonic assisted high-temperature cooking extraction method of soluble dietary fiber from bamboo shoots was optimized by response surface methodology, and the effects of ultrasonic assisted high-temperature cooking extraction on the structural characteristics, physicochemical properties and antioxidant activity of soluble dietary fiber (SDF) from bamboo shoots were evaluated. The yield of modified UH-SDF1 was significantly higher than that of untreated D-SDF2. FTIR and XRD confirmed that UH-SDF had more hydrophilic groups and higher crystallinity (28.73 %), resulting in better thermal stability. SEM observation showed that UH-SDF exhibited a more loose microstructure, and the particle size of UH-SDF (601.52 µm) was significantly smaller than that of D-SDF (242.59 µm), so UH-SDF had a larger specific surface area. In addition, UH-SDF has stronger water holding capacity, water swelling capacity and oil holding capacity than D-SDF. The DPPH radical and hydroxyl radical scavenging rates of UH-SDF were 8.91 % and 7.49 % higher than those of D-SDF. In addition, the reducing ability of UH-SDF was higher than that of D-SDF, which had better antioxidant activity. In summary, UH-SDF has the potential to be developed as an anti-inflammatory functional food.


Assuntos
Antioxidantes , Ultrassom , Antioxidantes/química , Temperatura , Fibras na Dieta/análise , Água/química , Culinária
3.
Microsyst Nanoeng ; 9: 20, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36844939

RESUMO

Ultrasonic fluid bubble detection is important in industrial controls, aerospace systems and clinical medicine because it can prevent fatal mechanical failures and threats to life. However, current ultrasonic technologies for bubble detection are based on conventional bulk PZT-based transducers, which suffer from large size, high power consumption and poor integration with ICs and thus are unable to implement real-time and long-term monitoring in tight physical spaces, such as in extracorporeal membrane oxygenation (ECMO) systems and dialysis machines or hydraulic systems in aircraft. This work highlights the prospect of capacitive micromachined ultrasonic transducers (CMUTs) in the aforementioned application situations based on the mechanism of received voltage variation caused by bubble-induced acoustic energy attenuation. The corresponding theories are established and well validated using finite element simulations. The fluid bubbles inside a pipe with a diameter as small as 8 mm are successfully measured using our fabricated CMUT chips with a resonant frequency of 1.1 MHz. The received voltage variation increases significantly with increasing bubble radii in the range of 0.5-2.5 mm. Further studies show that other factors, such as bubble positions, flow velocities, fluid medium types, pipe thicknesses and diameters, have negligible effects on fluid bubble measurement, demonstrating the feasibility and robustness of the CMUT-based ultrasonic bubble detection technique.

4.
Am J Transl Res ; 14(7): 4757-4767, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958452

RESUMO

BACKGROUND: Using continuous glucose monitoring (CGM) in critically ill adult patients requiring insulin therapy has increased with inconsistent results. Thus, we conducted a meta-analysis to assess the effect of CGM and frequent point-of-care (POC) measurements in such a patient population. METHODS: We searched PubMed, Embase, Cochrane Library, China national knowledge infrastructure, and Wanfang for relevant articles from inception to Jan 15, 2022. Randomized controlled trials (RCTs) were considered if they focused on critically ill patients who required insulin and were treated with CGM or any POC measurements. We used the Cochrane risk evaluating tool to assess study quality. Subgroup analysis and publication bias were also conducted. RESULTS: We finally included 19 RCTs with 1,852 participants. The quality of the included studies were at a low to moderate levels. Overall, CGM devices significantly reduced hypoglycemia incidence (Risk ratio (RR) 0.35; 95% CI, 0.25-0.49; P<0.00001) than the POC measurement. Further subgroup and sensitivity analyses confirmed this result. The CGM group also had lower overall mortality (RR 0.54; 95% CI, 0.34-0.86; P=0.01), lower glucose variability, and nosocomial infection. The time in, below, or above target blood glucose range, insulin use, and length of stay in the ICU were comparable between the two groups. In addition, few studies provided data in favor of decreased nursing workload and medical costs in the CGM group. CONCLUSIONS: The CGM technique could significantly reduce hypoglycemia incidence, overall mortality, and glucose variability compared to POC measurement in critically ill patients. However, further large, well-designed RCTs are required to confirm our results.

5.
Sci Rep ; 12(1): 13112, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35908107

RESUMO

Field monitoring of foundation pits alone cannot predict the future deformation of retaining structures. Numerical simulations can predict the deformation of foundation pits and the working state of retaining structures to avoid the risk of foundation pit damage in advance. Accurate inversion of the soil parameters used for simulation and prediction is a key step. The associated multivariable problem is transformed into a single-variable problem by using the interval influence coefficient. Soil layer weightings and excavation step weightings are introduced and exploited to optimize the calculation process, and the soil parameters are calculated through inversion based on the least squares method. Based on actual engineering, the excavation sequence is regarded as a progressive sequence for back analysis, and the parameters of each soil layer are calculated through dynamic calculations with the excavation process in a cycle comprising inversion, prediction, reinversion and reprediction. The soil parameters after inversion are used to predict the maximum value and the depth of the deep horizontal displacement of the retaining structure, which verified the feasibility of the back-analysis method. Compared with the results before inversion, after the final inversion, t the overall error of section 2 is reduced by 67.24%, the overall error of section 3 is reduced by 40.5%, and the overall error of section 4 is reduced by 35%. The prediction curves are all close to the monitoring displacement curves, which plays a good guiding role and ensures the safe construction of the foundation pit. A new effective idea is proposed for the inverse analysis of the composite formation parameters of the deep foundation pit engineering.

6.
Mar Drugs ; 20(2)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35200635

RESUMO

Within the Conidae family, the piscivorous Conus species have been a hotspot target for drug discovery. Here, we assess the relevance of Conus and their other feeding habits, and thus under distinctive evolutionary constraints, to highlight the potential of neglected molluscivorous and vermivorous species in biomedical research and pharmaceutical industry. By singling out the areas with inadequate Conus disquisition, such as the Tamil Nadu Coast and the Andaman Islands, research resources can be expanded and better protected through awareness. In this study, 728 Conus species and 190 species from three other genera (1 from Californiconus, 159 from Conasprella and 30 from Profundiconus) in the Conidae family are assessed. The phylogenetic relationships of the Conidae species are determined and their known feeding habits superimposed. The worm-hunting species appeared first, and later the mollusc- and fish-hunting species were derived independently in the Neogene period (around 23 million years ago). Interestingly, many Conus species in the warm and shallow waters become polyphagous, allowing them to hunt both fish and worms, given the opportunities. Such newly gained trait is multi originated. This is controversial, given the traditional idea that most Conus species are specialized to hunt certain prey categories. However, it shows the functional complexity and great potential of conopeptides from some worm-eating species. Pharmaceutical attempts and relevant omics data have been differentially obtained. Indeed, data from the fish-hunting species receive strong preference over the worm-hunting ones. Expectedly, conopeptides from the fish-hunting species are believed to include the most potential candidates for biomedical research. Our work revisits major findings throughout the Conus evolution and emphasizes the importance of increasing omics surveys complemented with further behavior observation studies. Hence, we claim that Conus species and their feeding habits are equally important, highlighting many places left for Conus exploration worldwide. We also discuss the Conotoxin drug discovery potentials and the urgency of protecting the bioresources of Conus species. In particular, some vermivorous species have demonstrated great potential in malaria therapy, while other conotoxins from several worm- and mollusc-eating species exhibited explicit correlation with SARS-CoV-2. Reclaiming idle data with new perspectives could also promote interdisciplinary studies in both virological and toxicological fields.


Assuntos
Caramujo Conus/fisiologia , Comportamento Alimentar , Venenos de Moluscos/toxicidade , Animais , Antivirais/química , Antivirais/farmacologia , Caramujo Conus/genética , Humanos , Venenos de Moluscos/química , SARS-CoV-2/efeitos dos fármacos
7.
Front Med (Lausanne) ; 9: 1059747, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36698812

RESUMO

Objective: Bioelectrical impedance-derived phase angle (PA) has exhibited good prognostic values in several non-critical illnesses. However, its predictive value for critically ill patients remains unclear. Thus, we aimed to perform a systematic review and meta-analysis to investigate the relationship between PA and survival in such a patient population. Materials and methods: We searched for relevant studies in PubMed, Embase, and the Cochrane database up to Jan 20, 2022. Meta-analyses were performed to determine the association between the baseline PA after admission with survival. We further conducted subgroup analyses and sensitivity analyses to explore the sources of heterogeneity. Results: We included 20 studies with 3,770 patients. Patients with low PA were associated with a significantly higher mortality risk than those with normal PA (OR 2.45, 95% CI 1.97-3.05, P < 0.00001). Compared to survivors, non-survivors had lower PA values (MD 0.82°, 95% CI 0.66-0.98; P < 0.00001). Similar results were also found when pooling studies reported regression analyses of PA as continuous (OR = 0.64; 95% CI 0.52-0.79, P < 0.00001) or categorical variable (OR = 2.42; 95% CI 1.76-3.34; P < 0.00001). These results were further confirmed in subgroup analyses and sensitivity analyses. Conclusion: Our results indicated that PA may be an important prognostic factor of survival in critically ill patients and can nicely complement the deficiencies of other severity scoring systems in the ICU setting.

8.
Front Nutr ; 9: 1102671, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36712536

RESUMO

In this study, the physicochemical properties, thermal characteristics, and in vitro hypoglycemic activity of dietary fibers extracted from four bamboo shoots were characterized and compared. The results showed that Dendrocalamus brandisii Munro (C-BSDF) had the highest dietary fiber content (6.1%) and the smallest particle size (222.21 µm). SEM observations found that C-BSDF exhibited a loose and porous microstructure, while FTIR and XRD confirmed that C-BSDF had a higher degree of decomposition of insoluble dietary fiber components and the highest crystallinity, resulting in a better microstructure. Furthermore, C-BSDF exhibited excellent physiochemical properties with the highest water hold capacity, water swelling capacity, and preferable oil holding capacity. Thermal analysis showed that C-BSDF had the lowest mass loss (64.25%) and the highest denaturation temperature (114.03°C). The hypoglycemic activity of dietary fibers from bamboo shoots were examined in vitro and followed this order of activity: C-BSDF>D-BSDF>A-BSDF>B-BSDF. The inhibition ratios of GAC, GDRI and α-amylase activity of C-BSDF were 21.57 mmol/g, 24.1, and 23.34%, respectively. In short, C-BSDF display excellent physicochemical and functional properties due to its high soluble dietary fiber content, small particle size with a high specific surface area, and loose microstructure. Thus, D. brandisii Munro can be considered a promising new source of dietary fiber for hypoglycemic health products.

9.
Front Plant Sci ; 12: 731977, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539721

RESUMO

The mechanisms for physiological senescence in bamboo shoots after harvest remain unclear. This study investigated physiological changes in Fargesia yunnanensis shoots during storage at different temperatures. The relationship between morphological and physiological changes in bamboo shoots during storage was also analyzed. The results show that cold storage can reduce weight loss, browning, respiration rates, and sugar degradation in bamboo shoots; decrease related enzymatic activities; and inhibit the increase in lignin and cellulose content. The quality of bamboo shoots declines more during the first 3d after harvesting than it does during subsequent periods. The increase in the degree of lignification and fibrosis is the main reason for senescence and for the decline in quality of bamboo shoots after harvest. The bamboo shoots under RT conditions began browning during the third 3d of storage, with a browning rate of 688gkg-1 even in the upper parts; the increase in shoot browning degrees significantly decreased the quality. Low temperatures had better inhibitory effects on browning than they did on lignification and fibrosis. Nonstructural carbohydrates in bamboo shoots are degraded and flow into sheath and shoot respiration, phenols, and shoot fibrosis and lignification at room temperature, but only flow into sheath respiration, shoot fibrosis, and lignification at cold temperature. Soluble protein and free amino acids are primarily distributed into shoot and sheath respiration and into phenols at room temperature, but that process is well inhibited at cold temperature. Bamboo shoots, once removed from cold storage, should be consumed rapidly because enzyme activity recovers quickly. This research provides new theoretical information on the preservation of bamboo shoots.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33175678

RESUMO

Capacitive micromachined ultrasonic transducers (CMUTs) are promising in the emerging fields of personalized ultrasonic diagnostics, therapy, and noninvasive 3-D biometric. However, previous theories describing their mechanical behavior rarely consider multilayer and anisotropic material properties, resulting in limited application and significant analysis errors. This article proposes closed-form expressions for the static deflection, collapse voltage, and resonant frequency of circular-microplate-based CMUTs, which consider both the aforementioned properties as well as the effects of residual stress and hydrostatic pressure. These expressions are established by combining the classical laminated thin plate (CLTP) theory, Galerkin method, a partial expansion approach for electrostatic force, and an energy equivalent method. A parametric study based on finite-element method simulations shows that considering the material anisotropy can significantly improve analysis accuracy (~25 times higher than the theories neglecting the material anisotropy). These expressions maintain accuracy across almost the whole working voltage range (up to 96% of collapse voltages) and a wide dimension range (diameter-to-thickness ratios of 20-80 with gap-to-thickness ratios of ≤2). Furthermore, their utility in practical applications is well verified using numerical results based on more realistic boundary conditions and experimental results of CMUT chips. Finally, we demonstrate that the high accuracy of these expressions at thickness-comparable deflection results from the extended applicable deflection range of the CLTP theory when it is used for electrostatically actuated microplates.

11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(10): 1179-1182, 2020 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-32924130

RESUMO

OBJECTIVE: To analyze serological and molecular characteristics of a case with Bw11 subtype. METHODS: The ABO antigen and antibody in serum were respectively detected with the classical tube method, microcolumn gel method, and absorption and diffusion method. The ABO genotype was determined with PCR using sequence-specific primers (PCR-SSP). Exons 1-7 of the ABO gene were analyzed by Sanger sequencing. Haplotype analysis was carried out for exons harboring variants. RESULTS: Forward and reverse typing with the microcolumn gel method has suggested type O, while forward and reverse typing with the classical tube method yielded inconsistent results. Absorption and diffusion test confirmed presence of B antigen. Antibody screening excluded presence of alloantibodies. The result of PCR-SSP suggested a B/O1 genotype.A 695T>C variant was identified in exon 7 as compared with the B101/O01 allele, which resulted in conversion of Leucine to Proline at position 232, and was confirmed as Bw11/O1 heterozygote. CONCLUSION: The nt695T>C variant probably underlay the weakening of B antigenin the individual. There may be strong anti-B antibodies in Bw11 subtypes. Human-derived and certain monoclonal reagents may not detect Bw11 subtypes which is easy to be misjudged as type O. Application of molecular methods can identify ABO subtypes with accuracy.


Assuntos
Sistema ABO de Grupos Sanguíneos , Sistema ABO de Grupos Sanguíneos/genética , Alelos , Sequência de Bases , Éxons/genética , Genótipo , Humanos , Fenótipo
12.
Exp Ther Med ; 18(5): 3823-3828, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31602249

RESUMO

The aim of the present study was to investigate the potential of the Immuknow immune cell function assay for the diagnosis of infection after pediatric living-donor liver transplantation (LDLT). Based on clinical data obtained following liver transplantation, 66 patients were divided into infection (n=28) and non-infection (n=38) groups. The following factors were considered in the present analysis: Primary disease, lymphocyte count, tacrolimus plasma concentration/dose (C0/D) ratio, CD4+ T lymphocyte ATP levels, at pre-transplant stage and at weeks 1-4, and 2 and 3 months post-transplant. The CD4+ T lymphocyte ATP values were plotted in a receiver operating characteristic (ROC) curve. The CD4+ T lymphocyte ATP value of the infection group was significantly lower compared with that of the non-infection group (188.6±93.5 vs. 424.4±198.1 ng/ml, respectively; P<0.05). No correlation was observed between the ATP value and tacrolimus plasma C0/D ratio (R2=0.0001484); however, a correlation was reported between the ATP value and lymphocyte count (R2=0.2149). Analysis of the ROC curve indicated that the ATP levels of CD4+ T cells were significantly associated with the diagnostic value of infection (area under the curve=0.866). These findings suggest that low CD4+ T lymphocyte ATP levels may be an independent risk factor for infection following pediatric LDLT, and that the Immuknow assay may be used as a tool to evaluate T lymphocyte function in such patients to predict the risk of infection.

13.
Rev Sci Instrum ; 90(6): 064901, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31255016

RESUMO

In many situations, it is essential to analyze a nonstationary signal for sensing whose components not only overlapped in time-frequency domain (TFD) but also have different durations. In order to address this issue, an improved separation method based on the time-frequency distribution is proposed in this paper. This method computes the time-frequency representation (TFR) of the signal and extracts the instantaneous frequency (IF) of components by a two-dimensional peak search in a limited area in which normalized energy is greater than the set threshold value. If there is more than one peak from a TFR, IFs of components can be determined and linked by a method of minimum slope difference. After the IFs are obtained, the improved time-frequency filtering algorithm is used to reconstruct the component of the signal. We continue this until the residual energy in the TFD is smaller than a fraction of the initial TFD energy. Different from previous methods, the improved method can separate the signal whose components overlapped in TFR and have different time durations. Simulation results have shown the effectiveness of the proposed method.

14.
Int J Biol Macromol ; 126: 376-384, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30593808

RESUMO

Isolation of earth abundant biopolymer, Lignin, from Dendrocalamus sinicus and their structural properties were investigated to achieve its large-scale practical applications in value-added products. Two lignin fractions (MWL, DSL) were isolated with successive treatments of dioxane and dimethylsulfoxide (DMSO) from dewaxed and ball milled bamboo (D. sinicus) sample. The two-step treatments yielded 52.1% lignin based on the total lignin content in the dewaxed bamboo sample. Spectroscopy analyses indicated that the isolated bamboo lignin was a typical grass lignin, consisting of p-hydroxyphenyl, guaiacyl, and syringyl units. The major interunit linkages presented in the obtained bamboo lignin were ß-O-4' aryl ether linkages, together with lower amounts of ß-ß', ß-5', and ß-1' linkages. The tricin was detected to be linked to lignin polymer through the ß-O-4' linkage in the bamboo. In addition, phenyl glycoside and benzyl ether lignin-carbohydrate complexes (LCC) linkages were clearly detected in bamboo (D. sinicus), whereas the γ-ester LCC linkages were ambiguous due to the overlapping NMR signals with other substructures. The detailed structural properties of the obtained lignin fraction together with the light-weight will benefit efficient utilization of natural polymers as a possibly large-scale bio-based precursor for making polymeric materials, biochemicals, functional carbon and biofuels, and multifunctional polymer nanocomposites.


Assuntos
Carboidratos/isolamento & purificação , Lignina/química , Poaceae/química , Carboidratos/química , Espectroscopia de Ressonância Magnética , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Metabolism ; 82: 36-46, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29289515

RESUMO

OBJECTIVE: Obese adipose tissue has been characterized with chronic inflammation associated with elevated secretion of inflammatory cytokines and declined secretion of anti-inflammatory cytokines which can impair endothelial function in an endocrine manner. Adipose tissue hypoxia plays a role in the changes of cytokines. Physical exercise/muscle contraction may help preventing cardiovascular disease through improving insulin resistance and endothelium function. However the mechanism is unclear. Skeletal muscle is an endocrine tissue. Contracting muscles secrete myokines which may play roles in the beneficial effect of exercise. In this study, the conditioned medium from electrical pulse stimulation (EPS) regulated skeletal muscle cells was used to explore the mechanism of contraction on endothelial dysfunction and insulin resistance induced by conditioned medium from hypoxic adipocytes. METHODS: 3T3-L1 adipocytes were incubated under normoxia or hypoxia condition, respectively. The supernatant was collected as adipocyte conditioned medium (CM-N and CM-H). C2C12 mouse skeletal muscle cells were stimulated with EPS for 12 h. The supernatant was collected as muscle cells conditioned medium (CM-EPS). Human umbilical vein endothelial cells (HUVECs) were incubated with adipocyte CM and muscle cells CM together. Macrophages migration to HUVECs was detected with transwell system. The mRNA expressions of E-selectin, ICAM-1, MCP-1 and IL-6 were measured by real-time PCR. The phosphorylation of IKKα/ß, NF-κB, Akt, AMPK, eNOS and SOCS3 protein levels were detected by Western blot. Concentration of NO was measured by ELISA kit. HUVECs apoptosis was detected by flow cytometry. RESULTS: CM-EPS reduced the increase of mRNA expressions of E-selectin, ICAM-1, MCP-1 and IL-6 in HUVECs induced by CN-H. The phosphorylations of IKKα/ß and NF-κB, SOCS3 protein level and endothelial cells apoptosis, which were raised by CM-H, were significantly reduced by CM-EPS. CM-EPS reversed the effects of CM-H on Akt and eNOS phosphorylations and NO production in HUVECs. CM-EPS directly stimulated the phosphorylation of AMPK, which caused the following phosphorylation of eNOS in HUVECs. CONCLUSION: In summary, CM-EPS reversed endothelial cells inflammation, apoptosis, insulin resistance and dysfunction induced by CM-H.


Assuntos
Adipócitos/citologia , Meios de Cultivo Condicionados , Resistência à Insulina/fisiologia , Contração Muscular/fisiologia , Fibras Musculares Esqueléticas/citologia , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Selectina E/metabolismo , Estimulação Elétrica , Quinase I-kappa B/metabolismo , Camundongos , Fibras Musculares Esqueléticas/metabolismo , NF-kappa B/metabolismo
16.
Biochem Biophys Res Commun ; 495(2): 1956-1963, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29247648

RESUMO

Exercise/muscle contraction increases cell surface glucose transporter 4 (GLUT4), leading to glucose uptake to regulate blood glucose level. Elevating cytosolic Ca2+ mediates this effect, but the detailed mechanism is not clear yet. We used calcium ionophore ionomycin to raise intracellular cytosolic Ca2+ level to explore the underlying mechanism. We showed that in L6 myoblast muscle cells stably expressing GLUT4myc, ionomycin increased cell surface GLUT4myc levels and the phosphorylation of AS160, TBC1D1. siPKCα and siPKCθ but not siPKCδ and siPKCε inhibited the ionomycin-increased cell surface GLUT4myc level. siPKCα, siPKCθ inhibited the phosphorylation of AS160 and TBC1D1 induced by ionomycin. siPKCα and siPKCθ prevented ionomycin-inhibited endocytosis of GLUT4myc. siPKCθ, but not siPKCα inhibited ionomycin-stimulated exocytosis of GLUT4myc. siRab13 but not siRab8a, siRab10 and siRab14 inhibited the exocytosis of GLUT4myc promoted by ionomycin. In summary, ionomycin-promoted exocytosis of GLUT4 is partly reversed by siPKCθ, whereas ionomycin-inhibited endocytosis of GLUT4 requires both siPKCα and siPKCθ. PKCα and PKCθ contribute to ionomycin-induced phosphorylation of AS160 and TBC1D1. Rab13 is required for ionomycin-regulated GLUT4 exocytosis.


Assuntos
Sinalização do Cálcio/fisiologia , Endocitose/fisiologia , Exocitose/fisiologia , GTP Fosfo-Hidrolases/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Mioblastos/fisiologia , Proteína Quinase C/metabolismo , Animais , Cálcio/metabolismo , Ionóforos de Cálcio/administração & dosagem , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular , Endocitose/efeitos dos fármacos , Exocitose/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Ionomicina/administração & dosagem , Mioblastos/efeitos dos fármacos , Transporte Proteico/fisiologia , Ratos
17.
Int J Legal Med ; 131(1): 115-117, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27448570

RESUMO

To study the population data of Y-chromosome STRs (Y-STRs) of Han population resided in Hunan province, we analyzed haplotypes of 26 Y-STRs (DYS19, DYS385a/b, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS481, DYS533, DYS549, DYS570, DYS576, DYS635, DYS643, DYS388, DYS449, DYS460, and YGATAH4) in 310 unrelated male individuals using a commercially available Goldeneye® DNA ID 26Y system. The calculated average gene diversity values ranged from 0.4211 to 0.9590 for DYS438 and DYS385a/b loci, respectively. The discriminatory capacity was 96.77 % with 300 observed haplotypes. Population relationships between Hunan Han and eight other populations available from Y-chromosome haplotype reference database (YHRD) were compared. The results showed that the Han population resided in the Hunan district is significantly different from other populations. Our results also indicated that these 26 Y-STR loci were highly genetically polymorphic in the Hunan Han population and of great value in forensic application.


Assuntos
Cromossomos Humanos Y , Etnicidade/genética , Genética Populacional , Repetições de Microssatélites , China , Impressões Digitais de DNA , Frequência do Gene , Variação Genética , Humanos , Masculino
18.
Biochem Biophys Res Commun ; 478(1): 46-52, 2016 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-27457805

RESUMO

PURPOSE: Liraglutide, a glucagon-like peptide-1 (GLP-1) analogue, is an antidiabetic drug. It has been shown to improve endothelial dysfunction, but the mechanism remains somewhat unclear. Leptin can also improve endothelial function. Cardiovascular disease (CVD) is linked to hyperleptinemia, and leptin resistance, how liraglutide influences the effect of leptin on endothelial function, is never reported. We used palmitic acid (PA) to mimic hyperlipidemia in endothelial cells to explore the cardio-protective mechanism of liraglutide and its impact on the role of leptin. METHODS: Human umbilical vein endothelial cells (HUVECs) were incubated with PA for 16 h and then were treated with liraglutide for 30 min. RESULTS: PA elevated not only phosphorylation of JNK and IKKα/ß, but also the expression of IL-6 in HUVECs. These effects of PA were reversed by liraglutide. In addition, liraglutide increased phosphorylation of eNOS, AMPK, and the release of NO but had no effect on PKC phosphorylation. In addition, leptin elevated eNOS phosphorylation but was abrogated by PA. However, in the presence of liraglutide, leptin regained its function of elevating eNOS phosphorylation. Last, we found that liraglutide inhibited PA-elevated SOCS3, which is a marker of leptin resistance. CONCLUSIONS: GLP-1 impairs endothelial inflammatory signals, improves endothelial function, and reverses leptin resistance.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Células Endoteliais/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Leptina/metabolismo , Liraglutida/farmacologia , Ácido Palmítico/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/metabolismo , Hiperlipidemias/patologia
19.
J Basic Microbiol ; 56(2): 184-95, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26576943

RESUMO

Bioemulsifiers can be applicated in a variety of areas such as bioremediation and microbial-enhanced oil recovery. The present study was aimed at bioemulsifier production, optimization, stability studies, and applications of the bioemulsifier produced by one of these strains, Acinetobacter beijerinckii ZRS. When Acinetobacter beijerinckii ZRS is cultured with hexadecane as a carbon source, it produces a novel extracellular emulsifying agent that does not cause remarkable reductions in surface tension. In order to enhance bioemulsifier production, response surface methodology was applied to optimize the culture medium. The bioemulsifier was subjected to thin-layer chromatography, Fourier transform infrared spectroscopy (FTIR), gel filtration chromatography, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF), and nuclear magnetic resonance (NMR), which allowed for the identification of a novel polymeric bioemulsifier. The bioemulsifier retained its properties at a wide range of pH values, high temperatures and high salinities (up to 5% [w/v] Na(+) and 24% Ca(2+)). To deduce the role of this bioemulsifier in a coastal zone oil spill, the propagation of oil-degrading bacteria on oil-coated grains of gravel immersed in seawater was investigated in beach-simulating tanks. The bioemulsifier played a positive role in the degradation of these hydrocarbons and increasing the light crude oil degradation rate of the bacterial strain from 37.5 to 58.3% within 56 days. Therefore, this bioemulsifier shows strong potential to be used for bioremediation of oil pollution in marine environments.


Assuntos
Acinetobacter/metabolismo , Emulsificantes/isolamento & purificação , Emulsificantes/metabolismo , Petróleo/metabolismo , Alcanos/metabolismo , Carbono/metabolismo , Cromatografia em Gel , Cromatografia em Camada Delgada , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Salinidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
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