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1.
J Hypertens ; 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32384389

RESUMO

BACKGROUND: Regular exercise is a lifestyle intervention for controlling hypertension and has an improving effect on vascular function. Voltage-gated L-type Ca (LTCC) and large-conductance Ca-activated K (BKCa) channels are two principal mediators of vascular smooth muscle cell contractility and arterial tone. The present study tested the hypothesis that DNA methylation dynamics plays a key role in exercise-induced reprogramming and downregulation of LTCC and BKCa channel in mesenteric arteries from spontaneously hypertensive rats (SHRs). METHODS: SHRs and Wistar-Kyoto (WKY) rats were subjected to exercise training or kept sedentary, and vascular molecular and functional properties were evaluated. RESULTS: Exercise inhibited hypertension-induced upregulation of LTCC and BKCa channel function in mesenteric arteries by repressing LTCC α1c and BKCa ß1 subunit expression. In accordance, exercise triggered hypermethylation of α1c and ß1 gene in SHR, with concomitant decreasing TET1, increasing DNMT1 and DNMT3b expression in mesenteric arteries, as well as altering peripheral α-KG and S-adenosylmethionine/ S-adenosylhomocysteine ratio. Acting synergistically, these exercise-induced functional and molecular amelioration could allow for attenuating hypertension-induced elevation in arterial blood pressure. CONCLUSION: Our results indicate that exercise suppresses LTCC and BKCa channel function via hypermethylation of α1c and ß1 subunits, which contributes to the restoration of mesenteric arterial function and vasodilation during hypertension.

2.
Environ Pollut ; 264: 114674, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32375090

RESUMO

The strict environmental management has been implemented in Taihu Basin to reduce the surface water contamination; however, the effectiveness of the management actions has not been comprehensively evaluated. In the present study, 364 samples were collected during four campaigns over a span of one year from surface water, municipal wastewater treatment plants (MWWTPs), industrial wastewater treatment plants (IWWTPs), industrial enterprises, and aquaculture in a typical region in the Upper Taihu Basin. Overall concentration, temporal variation and spatial distribution of 16 PAHs in surface water and various pollution sources were evaluated and the potential pollution sources were identified. Results showed that concentrations of individual PAHs in the surface water ranged from less than the limit of quantification (LOQ) to 949 ng L-1, indicating a reduction of PAH contamination level after the implementation of environmental management actions. Influent of MWWTPs and wastewater from industrial enterprises exhibited relatively high ∑PAHs concentrations (mean: 880 ng L-1 and 642 ng L-1, respectively); these samples also exhibited a similar seasonal variation as well as composition of PAH congeners to those found in surface water, and therefore were designated as the main emission sources of PAHs in the studied region. Additional source apportionment using principal component analysis was also conducted to verify the proposed sources and diagnose other pollution sources. The findings provided a thorough understanding of PAH pollution, especially its major emission sources, in a typical region with pollution-intensive industries after the implementation of strict environmental management.

3.
Meat Sci ; 165: 108136, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32272341

RESUMO

In this study, pH, meat color analysis, microbial counts and Raman spectroscopic data were obtained from beef steaks stored at 4 °C for up to 21 days using two different packaging methods: vacuum (VP) and modified atmosphere packaging (MAP). Models using partial least square regression (PLSR), indicated that Raman spectroscopy was able to predict total viable counts (TVC) and lactic acid bacteria (LAB) measured at 21d post mortem (TVC in VP: R2cv = 0.99, RMSEP = 0.61; TVC in MAP: R2cv = 0.90, RMSEP = 0.38; LAB in VP: R2cv = 0.99, RMSEP = 0.54; LAB in MAP: R2cv = 0.75, RMSEP = 0.60). The results of this study demonstrate that Raman spectroscopy may have potential for the rapid determination of meat spoilage.

4.
Acupunct Med ; : 964528420912248, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32310010

RESUMO

OBJECTIVE: To investigate the regulatory mechanism of manual acupuncture (MA) on microglial polarization-mediated neuroinflammation after traumatic brain injury (TBI), focusing on the RhoA/Rho-associated coiled coil-forming protein kinase (ROCK2) pathway. METHODS: Sprague Dawley (SD) rats were used to generate a TBI model using Feeney's freefall epidural impact method. MA was performed on half of the TBI model rats, while the others remained untreated. Acupuncture was administered at GV15, GV16, GV20, GV26, and LI4. At the end of the intervention, rat brain tissue samples were collected, and the microglial M1 polarization status was observed by immunofluorescence labeling of CD86, an M1 microglia-specific protein. RhoA/ROCK2 signaling components were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. An enzyme-linked immunosorbent assay (ELISA) was used to detect the expression levels of inflammatory factors. RESULTS: Compared with normal rats, the CD86 expression density in the untreated TBI model rats was high and showed an aggregated expression pattern. The genes and proteins of the RhoA/ROCK2 signaling pathway were highly expressed, and inflammatory factors were significantly increased. The CD86 expression density in TBI rats after MA was reduced compared to that in untreated TBI rats and showed a scattered distribution. The expression of RhoA/ROCK2 signaling pathway genes and proteins was also significantly reduced, and inflammatory factors were decreased. CONCLUSION: These results show that MA may inhibit M1 polarization of microglia by regulating the RhoA/ROCK2 signaling pathway, thereby reducing neuroinflammation in TBI.

6.
J Tradit Chin Med ; 40(2): 267-274, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32242392

RESUMO

OBJECTIVE: To evaluate the effect of acupuncture on neuroinflammation in traumatic brain injury (TBI) rats by stimulating Yamen (GV 15), Fengfu (GV 16), Baihui (GV 20), Shuigou (GV 26) and Hegu (LI 4) acupoints and to investigate the mechanism underpinning this effect. METHODS: A TBI model was induced in Sprague- Dawley rats using Feeney's freefall impact method. Acupuncture to stimulate the Yamen (GV 15), Fengfu (GV 16), Baihui (GV 20), Shuigou (GV 26) and Hegu (LI 4) acupoints was performed on the TBI rats. After 3 consecutive days of acupuncture treatment, we investigated signal molecules, receptors and microglia related to neuroinflammation in brain tissue of the TBI rats and analyzed the possible mechanism underlying the effect of acupuncture on neuroinflammation. RESULTS: After the acupuncture treatment, ionized calcium binding adaptor molecule 1(Iba1), a protein specific to microglia, was investigated. In the cortical layer of damaged brain tissue in TBI rats, the Iba1-positive area was 3.3% ± 0.9% in the rats that received acupuncture compared with 5.2% ± 1.4% in the TBI rats that did not receive acupuncture, and the microglia were smaller with more slender protrusions in the acupuncture-treated rats. This result indicates that acupuncture can significantly reduce microglia activation in TBI rats. A possible mechanism for this effect is that acupuncture reduces the expression of autotaxin and lysophosphatidic acid. Together, these constitute the autotaxin-lysophosphatidic acid axis, which induces microglial activation in the brains of TBI rats. Acupuncture treatment may downregulate the expression of Lysophosphatidic acid (LPA) receptor (LPAR) 1 and LPAR2 on the microglial cytomembrane, which affects the microglia activation process. CONCLUSION: Acupuncture stimulating the Yamen (GV 15), Fengfu (GV 16), Baihui (GV 20), Shuigou (GV 26) and Hegu (LI 4) acupoints can effectively inhibit the development of neuroinflammation after TBI. One possible mechanism for this effect is that acupuncture downregulates LPA synthesis and affects the LPA-LPAR pathway by inhibiting LPAR1 and LPAR2, thereby inhibiting microglial activation and reducing neuroinflammation.

7.
Food Res Int ; 130: 108937, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32156384

RESUMO

This study explored the shelf-life and bacterial community dynamics of beef cuts stored at super-chilled conditions (-1 ± 0.5 °C) for 20 weeks when sourced from two Chinese abattoirs, in order to determine whether domestic beef has equivalent quality as that imported from Australia. The initial total viable counts (TVC) were 4.15 and 4.87 log CFU/cm2 in beef from abattoirs A and B, respectively at the commencement of the storage period. The TVC of beef from abattoir A was above 6.0 log CFU/cm2 at 6 weeks and kept below 7.0 log CFU/cm2 at 20 weeks; while the counts were above 6.0 log CFU/cm2 at 3 weeks and reached at 7.3~7.6 log CFU/cm2 in beef from abattoir B. The beef shelf-life was deemed less than 12 and 9 weeks in abattoirs A and B, respectively, based on the total volatile basic nitrogen (TVBN) threshold, although all samples were acceptable organoleptically. High-throughput sequencing showed that the initial bacteria community and bacterial succession during storage were different between the two abattoirs. Carnobacterium spp. and Lactobacillus spp. dominated in both abattoirs throughout 3-9 weeks while Serratia spp. co-dominated in abattoir B, and Lactobacillus spp. and Carnobacterium spp. were dominant for the rest of storage in abattoir A and B, respectively. Overall, the high initial TVC is a concern compared to imported beef from Australia. To achieve comparable shelf-life, domestic super-chilled stored beef would need to be sourced from abattoirs employing effective decontamination technologies or where strict hygiene procedures are adopted.

8.
Clin Infect Dis ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32211844

RESUMO

BACKGROUND: The outbreak of COVID-19 has become a big threat to China, with high contagious capacity and varied mortality. This study aimed to investigate the epidemiological and clinical characteristics of older patients with COVID-19 out of Wuhan. METHODS: A retrospective study was performed, with collecting data from medical records of confirmed COVID-19 patients in Zhejiang province from Jan 17 to Feb 12, 2020. Epidemiological, clinical and treatment data were analyzed between those older (≥60y) and younger (<60y) patients. RESULTS: Total 788 patients with confirmed COVID-19 were selected, where 136 were older patients with corresponding age of 68.28y±7.314y. There was a significantly higher frequency of women in the older patients compared with the younger patients (57.35% vs 46.47%, P=0.021). The presence of coexisting medical condition was significantly higher in older patients compared with younger patients (55.15% vs 21.93%, P<0.001), including the rate of hypertension, diabetes, heart diseases and COPD. Significantly higher rates of severe (older vs younger groups: 16.18% vs 5.98%, P<0.001)/critical (8.82% vs 0.77%, P<0.001) type, shortness of breath (12.50% vs 3.07%, P<0.001) and high temperature of >39.0℃ (13.97% vs 7.21%, P=0.010) were observed in older patients compared with younger patients. Finally, Higher rates of ICU admission (9.56% vs 1.38%, P<0.001) and methylprednisolone application (28.68% vs 9.36%, P<0.001) were also identified in older patients. CONCLUSIONS: The specific epidemiological and clinical features of older COVID-19 patients included significantly higher female gender, body temperature, co-existing of basic diseases and rate of severe and critical type.

9.
Sci Total Environ ; 722: 137946, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32208277

RESUMO

A comprehensive characterisation of four phenolic compounds in surface water and various emission sources was conducted simultaneously in a typical industrial city upstream of the Taihu Lake watershed. The overall concentrations of the target compounds ranged from 0.15 to 2.75 µg/L in the surface water and from 0.43 to 377 µg/L in the emission sources. Relatively high concentration levels were observed in August, during which the rainy season typically occurred in the study area, indicating seasonal emission sources. The spatial distribution revealed severe phenolic-compound contamination in the northeast part of the study area. According to the relationships between the surface water and emission sources, combined-sewer overflow and surface runoff from agricultural activities were identified as seasonal emission sources that were responsible for the increased concentration levels in wet seasons. Indirect discharge of industrial wastewater was proposed as a persistent emission source responsible for the severe contamination level in the northeast region over the entire sampling period, accounting for 16.5% of the phenolic-compound load in a demonstration river section. The findings of this study are useful for identifying the sources of phenolic compounds and controlling the contamination from the main sources in a typical industrial city.

10.
Gut ; 69(6): 1002-1009, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32213556

RESUMO

OBJECTIVE: The SARS-CoV-2-infected disease (COVID-19) outbreak is a major threat to human beings. Previous studies mainly focused on Wuhan and typical symptoms. We analysed 74 confirmed COVID-19 cases with GI symptoms in the Zhejiang province to determine epidemiological, clinical and virological characteristics. DESIGN: COVID-19 hospital patients were admitted in the Zhejiang province from 17 January 2020 to 8 February 2020. Epidemiological, demographic, clinical, laboratory, management and outcome data of patients with GI symptoms were analysed using multivariate analysis for risk of severe/critical type. Bioinformatics were used to analyse features of SARS-CoV-2 from Zhejiang province. RESULTS: Among enrolled 651 patients, 74 (11.4%) presented with at least one GI symptom (nausea, vomiting or diarrhoea), average age of 46.14 years, 4-day incubation period and 10.8% had pre-existing liver disease. Of patients with COVID-19 with GI symptoms, 17 (22.97%) and 23 (31.08%) had severe/critical types and family clustering, respectively, significantly higher than those without GI symptoms, 47 (8.14%) and 118 (20.45%). Of patients with COVID-19 with GI symptoms, 29 (39.19%), 23 (31.08%), 8 (10.81%) and 16 (21.62%) had significantly higher rates of fever >38.5°C, fatigue, shortness of breath and headache, respectively. Low-dose glucocorticoids and antibiotics were administered to 14.86% and 41.89% of patients, respectively. Sputum production and increased lactate dehydrogenase/glucose levels were risk factors for severe/critical type. Bioinformatics showed sequence mutation of SARS-CoV-2 with m6A methylation and changed binding capacity with ACE2. CONCLUSION: We report COVID-19 cases with GI symptoms with novel features outside Wuhan. Attention to patients with COVID-19 with non-classic symptoms should increase to protect health providers.


Assuntos
Betacoronavirus , Técnicas de Laboratório Clínico , Infecções por Coronavirus , Trato Gastrointestinal , Pandemias , Pneumonia Viral , Adulto , China , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/virologia , Feminino , Trato Gastrointestinal/fisiopatologia , Trato Gastrointestinal/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/fisiopatologia , Pneumonia Viral/virologia , Fatores de Risco
11.
Int J Infect Dis ; 94: 81-87, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32205284

RESUMO

PURPOSE: To investigate the epidemiological and clinical characteristics of COVID-19 patients with abnormal imaging findings. METHODS: Patients confirmed with SARS-CoV-2 infection in Zhejiang province from January 17 to February 8 who had undergone CT or X-ray were enrolled. Epidemiological and clinical data were analyzed among those with abnormal or normal imaging findings. RESULTS: Excluding 72 patients with normal images, 230 of 573 patients showed abnormalities affecting more than two lung lobes. The median radiographic score was 2.0, and there was a negative correlation between that score and the oxygenation index (ρ = -0.657, P < 0.001). Patients with abnormal images were older (46.65 ± 13.82), with a higher rate of coexisting condition (28.8%), a lower rate of exposure history, and longer time between onset and confirmation (5 days) than non-pneumonia patients (all P < 0.05). A higher rate of fever, cough, expectoration and headache, a lower level of lymphocytes, albumin, and serum sodium levels and a higher total bilirubin, creatine kinase, lactate dehydrogenase, and C-reactive protein levels and a lower oxygenation index were observed in pneumonia patients (all P < 0.05). Muscle ache, shortness of breath, nausea and vomiting, lower lymphocytes levels, and higher serum creatinine and radiographic score at admission were predictive factors for the severe/critical subtype. CONCLUSION: Patients with abnormal images have more obvious clinical manifestations and laboratory changes. Combing clinical features and radiographic scores can effectively predict severe/critical types.


Assuntos
Betacoronavirus , Infecções por Coronavirus/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Adulto , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Tosse/etiologia , Feminino , Febre/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Estudos Retrospectivos , Escarro , Adulto Jovem
13.
Artigo em Inglês | MEDLINE | ID: mdl-32041170

RESUMO

The judgment and assessment of remediation effect on urban black-odor river still depend on the physical-chemical parameters and lack in ecological safety effects. A set of combined biological toxicity tests were applied to evaluate the ecological effects of one urban black-odor river before and after the remediation. The special growth rate of Chlorella vulgaris and mortality rate of Daphnia magna were used to assess acute toxicity. The Salmonella Typhimurium/Reverse Mutation Assay was applied to test the mutagenicity. The tests by C. vulgaris growth showed that there was no inhibition before and after remediation by overlying water, in contrast promoted the growth of C. vulgaris. The tests by D. magna showed slight toxicity on site 3# before remediation and nontoxic after remediation. The mutagenicity of organic extracts from overlying water at all sampling sites were positive before remediation, but were eliminated after remediation except from 3 of 4 sites on TA98 strain. The addition of the liver microsomal S9 induced the positive mutagenicity on site 4# compared to S9 absence. The results clarified the applicable and the importance of the biological toxicity tests on assessing the remediation effect and potential ecological risk of urban black-odor river.

14.
Artigo em Inglês | MEDLINE | ID: mdl-32106656

RESUMO

Objective: This study was aimed to investigate the muscle-specific beef color stability at normal and high ultimate pHs. Methods: The impact of muscle ((longissimus lumborum; LL) vs. psoas major (PM)) and pH ((normal ultimate pH; Np) vs. high pH dark cutting beef (DC)) on color stability, indicated by basic color traits, metmyoglobin reducing activity and oxygen consumption (OC), as well as the lipid oxidation, were determined over 7 days of display at 4 °C. Results: DC-LL had the highest pH (6.92), followed by DC-PM (6.01), Np-PM (5.76) and Np-LL (5.52). DC-LL had increased (P < 0.05) a*, chroma and % OMb during display. DC-LL also had the highest metmyoglobin reducing activity and OC among all the samples, thus, the greatest color stability, although very dark throughout storage, with lowest values for lightness (L*) and yellowness (b*). Np-LL also exhibited relatively high color stability, as a result of its lower % MMb and OC and higher MRA than psoas muscle samples. The 0.2 unit difference of the pH between DC and Np psoas muscle, resulted in the difference of the color intensity, not the color stability. Interestingly, high pH psoas muscle (DC-PM) did not have better color stability than Np-PM, and in fact had lower color stability than even Np-LL. The similar level of OC and lipid oxidation cannot explain the difference in color stability between DC-PM and Np-LL. Conclusion: Dark cutting beef does not always show better color stability compared with normal pH beef, which depends on the muscle type. The balance of MRA and OC is important to keep the color in great intensity and stability in the meantime.

15.
Meat Sci ; 163: 108046, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31954335

RESUMO

Label-free proteomics was applied to understand the color and color stability development of dark cutting beef (DC). The color traits of DC (pH = 6.86) and normal beef (pH = 5.49) were determined during 7 days of display. DC had a lower redness and greater color stability, which was attributed to its higher deoxy-myoglobin content, greater oxygen consumption, as well as higher metmyoglobin reducing activity and lower lipid oxidation. A total of 28 differentially expressed mitochondrial proteins (fold change >1.8) between the two groups were identified, with 21 proteins overexpressed in DC mainly involved in oxidative phosphorylation, generation of reducing equivalent, TCA cycle and chaperones. These enhance the level of mitochondrial respiration, the stability of reducing MetMb and myoglobin and mitochondria function, leading to color characteristics of DC. Moreover, Glutaryl-CoA dehydrogenase was for the first time reported to be significantly associated with color parameters and its direct relationship with meat color is worthy investigation.

16.
Sci Total Environ ; 712: 136595, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31945541

RESUMO

A newly combined dewatered alum sludge (DAS) and neutralized used acid (NUA) biofilter has been constructed and investigated recently, aiming for improving nitrate (NO3--N) removal in simulated groundwater and exploring the spatiotemporal distribution of nirS and nosZ. The biofilter achieved 81.54% and 13.6 g N/ (m3 d) removal efficiency of NO3--N during the stabilization period. Spatiotemporal distributions of diversity and composition of nirS and nosZ varied approximately in two media with depths and time. Both DAS and NUA played important roles in attenuating nitrate because of predominant denitrifying genera functions, and the core differences were Rhodanobacter and Rhodobacter in DAS while Halomonas, Pseudogulbenkiania, and Cupriavidus in NUA. Acting as the strongly correlated genera, Magnetospirillum and Halomonas had a significantly positive or negative correlation with other dominant genera. Positive correlations existed among COD, TN, NO3--N, NO2--N, and both nirS and nosZ in the DAS filter, whereas the correlations were negative in the NUA filter. Particularly, the effluent concentration of NO3--N had a significantly negative correlation with the relative abundance of Rubrivivax and Pseudomonas. These results could be useful in adjusting the denitrification of nitrogen contaminants at the genetic level, especially in mitigating the influence of discharge of NO3--N on the process of groundwater restoration.


Assuntos
Água Subterrânea , Esgotos , Compostos de Alúmen , Desnitrificação , Nitratos , Nitrogênio
17.
Acta Haematol ; 143(1): 9-18, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31167182

RESUMO

BACKGROUND: Aggressive growth of primitive and immature cells in the bone marrow results in reductions in megakaryocyte and platelet (PLT) counts, leading to thrombocytopenia in acute myeloid leukemia (AML). However, not all AML patients show thrombocytopenia at the time of diagnosis, and the association of PLT count with patient survival is largely unknown. METHODS: A retrospective study was performed to determine PLT counts at diagnosis in the peripheral blood in 291 newly diagnosed AML patients and assess the association of PLT counts with the overall survival (OS) and disease-free survival (DFS) of these patients. RESULTS: Low PLT counts (≤40 × 109/L) were associated with better outcomes for the whole cohort (5-year OS, 55.1 ± 3.8 vs. 35.3 ± 3.5%, p < 0.001; 5-year DFS, 49.1 ± 3.8 vs. 25.7 ± 4.0%, p < 0.001) and intermediate-risk patients (5-year OS, 64.5 ± 5.4 vs. 41.0 ± 4.8%, p < 0.001; 5-year DFS, 60.8 ± 5.6 vs. 28.6 ± 5.6%, p < 0.001). Moreover, low PLT counts were related to deeper molecular remission. Low PLT counts correlated with better survival of intermediate-risk AML patients treated with chemotherapy only. Allogeneic hematopoietic stem cell transplantation attenuated the negative impact of high PLT counts on the survival of intermediate-risk patients. Furthermore, univariate and multivariate analyses demonstrated that PLT count at diagnosis was an independent prognostic factor for intermediate-risk AML. CONCLUSION: PLT count at diagnosis predicts survival for patients with intermediate-risk AML.

18.
J Colloid Interface Sci ; 561: 93-103, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31812870

RESUMO

Highly sensitive wearable textile pressure sensors represent the key components of smart textiles and personalized electronics, with potential applications in biomedical monitoring, electronic skin, and human-machine interfacing. Here, we present a simple and low-cost strategy to fabricate highly sensitive wearable textile pressure sensors for non-invasive human motion and physiological signal monitoring and the detection of dynamic tactile stimuli. The wearable textile sensor was woven using a one-dimensional (1D) weavable core-sheath nanofiber yarn, which was obtained by coating a Ni-coated cotton yarn electrode with carbon nanotube (CNT)-embedded polyurethane (PU) nanofibers using a simple electrospinning technique. In our design, the three-dimensional elastic porous nanofiber structure of the force-sensing layer and hierarchical fiber-bundled structure of the conductive Ni-coated electrode provide the sensor with a relatively large surface area, and a sufficient surface roughness and elasticity. This leads to rapid and sharp increases in the contact area under stimuli with low external pressure. As a result, the textile pressure sensor exhibits the advantages of a high sensitivity (16.52 N-1), wide sensing range (0.003-5 N), and short response time (~0.03 s). Owing to these merits, our textile-based sensor can be directly attached to the skin as usual and conformally fit the shape deformations of the body's complex flexible curved surfaces. This contributes to the reliable real-time monitoring of human movements, ranging from subtle physiological signals to vigorous movements. Moreover, a large-area textile sensing matrix is successfully fabricated for tactile mapping of spatial pressure by being worn on the surface of wrist, highlighting the tremendous potential for applications in smart textiles and wearable electronics.

19.
J Mater Chem B ; 8(2): 290-297, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31803882

RESUMO

Excess bilirubin in the body will lead to serious health problems; however, its efficient removal remains a challenge in the clinical field because the available sorbent materials still suffer from serious performance issues, performance declining in a high-content albumin environment. Herein, we prepared a novel polydopamine (PDA) decorated ordered mesoporous carbon (OMC) material for the efficient removal of bilirubin in albumin-rich conditions. OMC was used as the supporting material due to its high specific surface area and its good affinity to hydrophobic analytes. PDA was then decorated on the OMC material through a facile self-assembly process to form a surface-imprinted layer. The obtained PDA-coated OMC material (OMC@PDA) exhibited excellent adsorption performance towards bilirubin in albumin-free conditions, in which its theoretical maximum adsorption amount was calculated to be 513.54 mg g-1. The imprinted PDA layer, for which the association constant towards bilirubin reached 4.51 × 104 M-1, endowed OMC@PDA with a competitive affinity compared to albumin. Therefore the materials showed good adsorption capacity and efficiency even in an albumin-rich environment (the adsorption equilibrated at 122.7 mg g-1 in 30 min). In addition, the good biocompatibility of OMC@PDA was demonstrated by hemolysis assay and protein fouling evaluation, which indicated the feasibility of applying this material in clinical situations.

20.
Meat Sci ; 161: 108016, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31785514

RESUMO

During storage of vacuum packaged chilled beef (VPCB), lactic acid bacteria become the dominant microflora, facilitating an extended shelf life. However, at some point, (bio)chemical and organoleptic changes render the meat unacceptable. In this investigation we evaluated volatile and non-volatile metabolite changes in VPCB after 84-, 98-, 120- and 140-days storage at ~ - 1 °C. After 140-days storage, the sensory, volatile and non-volatile data did not indicate spoilage. Minimal changes in volatile signatures of collected weep and on raw and grilled steaks were measured. Changes in selected non-volatile components indicated increased proteolysis (free amino acids, carnosine) and changes in organic acids (lactic, succinic) and nucleotide metabolism. Rapid volatile profiling using proton transfer reaction mass spectrometry showed a clear progression of changes in selected compounds over the storage period. An increased concentration of ethanol and other compounds between 120 and 140 days, suggested that volatile changes may be a useful objective indicator of extended storage VPCB quality.

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