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1.
J Endocrinol ; 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31454789

RESUMO

Obesity and type 2 diabetes (T2D) are both complicated endocrine disorders resulting from an interaction between multiple predisposing genes and environmental triggers, while diet and exercise have key influence on metabolic disorders. Previous reports demonstrated that 2-aminoadipic acid (2-AAA), an intermediate metabolite of lysine metabolism, could modulate insulin secretion and predict T2D, suggesting the role of 2-AAA in glycolipid metabolism. Here, we showed that treatment of diet-induced obesity (DIO) mice with 2-AAA, significantly reduced body weight, decreased fat accumulation and lowered fasting glucose. Furthermore, Dhtkd1-/- mice, in which the substrate of DHTKD1 2-AAA increased to a significant high level, were resistant to DIO and obesity-related insulin resistance. Further study showed that 2-AAA induced higher energy expenditure due to increased adipocyte thermogenesis via up-regulating PGC1α and UCP1 mediated by ß3AR activation, and stimulated lipolysis depending on enhanced expression of hormone sensitive lipase (HSL) through activating ß3AR signaling. Moreover, 2-AAA could alleviate the diabetic symptoms of db/db mice. Our data showed that 2-AAA played an important role in regulating glycolipid metabolism independent of diet and exercise, implying that improving the level of 2-AAA in vivo could be developed as a strategy in the treatment of obesity or diabetes.

2.
Ecotoxicol Environ Saf ; 183: 109555, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31419699

RESUMO

In this study, we investigated the transformation of atenolol (ATL) by the naturally occurring laccase from Trametes versicolor in aqueous solution. Removal efficiency of ATL via laccase-catalyzed reaction in the presence of various laccase mediators was examined, and found that only the mediator 2, 2, 6, 6-tetramethyl-1-piperidinyloxy (TEMPO) was able to greatly promote ATL transformation. The influences of TEMPO concentration, laccase dosage, as well as solution pH and temperature on ATL transformation efficiency were tested. As TEMPO concentrations was increased from 0 to 2000 µM, ATL transformation efficiency first increased and then decreased, and the optimal TEMPO concentration was determined as 500 µM. ATL transformation efficiency was gradually increased with increasing laccase dosage. ATL transformation was highly pH-dependent with an optimum pH of 7.0, and it was almost constant over a temperature range of 25-50 °C. Humic acid inhibited ATL transformation through competition reaction with laccase. The presence of anions HCO3- and CO32- reduced ATL transformation due to both anions enhanced solution pHs, while Cl-, SO42-, and NO3- at 10 mM showed no obvious influence. The main transformation products were identified, and the potential transformation pathways were proposed. After enzymatic treatment, the toxicity of ATL and TEMPO mixtures was greatly reduced. The results of this study might present an alternative clean strategy for the remediation of ATL contaminated water matrix.

3.
Chem Commun (Camb) ; 55(74): 11056-11058, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31453575

RESUMO

Natural hollow fibers were used as templates to in situ produce thin Cs4PbX6 nanosheets on the inner walls, forming luminescent fibers that integrated the advantages of the large length of fibers and the emission tunability of perovskites, and exhibited great robustness as well for multiple applications like warning signs, anti-counterfeiting and fashion.

4.
Jpn J Radiol ; 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31401722

RESUMO

OBJECTIVES: To evaluate quantitative three-dimensional (3D) dynamic contrast-enhanced ultrasound (DCE-US) in the assessment of tumor angiogenesis using an orthotropic liver tumor model. METHODS: Nine New Zealand white rabbits with liver orthotropic VX2 tumors were established and imaged by two-dimensional (2D) and 3D DCE-US after SonoVue® bolus injections. The intraclass correlation coefficients of perfusion parameters, including peak intensity (PI), mean transit time, time to peak, and area under the curve, were calculated based on time-intensity curve. The percentage area of microvascular (PAMV) and the expression of vascular endothelial growth factor (VEGF) were both evaluated by immunohistochemical analysis and weighted by the tumor activity area ratio. Correlations between quantitative and histologic parameters were analyzed. RESULTS: The reproducibility of 3D DCE-US quantitative parameters was excellent (ICC 0.91-0.99); but only PI showed high reproducibility (ICC 0.97) in 2D. None of the parameters of quantitative 2D DCE-US were significantly correlated with weighted PAMV or VEGF. For 3D DCE-US, there was a positive correlation between PI and weighted PAMV (r = 0.74, P = 0.04) as well as VEGF (r = 0.79, P = 0.02). CONCLUSION: Quantitative parameters of 3D DCE-US show feasibility, higher reproducibility and accuracy for the assessment of tumor angiogenesis using an orthotropic liver tumor model compared with 2D DCE-US.

5.
J Pediatr ; 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31277900

RESUMO

OBJECTIVES: To determine if children with congenital heart disease (CHD) have lower newborn T-cell receptor excision circles (TREC) levels than the general population and to evaluate if low TREC levels in newborns with CHD are associated with clinical complications such as hospitalization for infection. STUDY DESIGN: The Connecticut Newborn Screening Program reported TREC levels for newborns with CHD delivered between October 2011 and September 2016 at 2 major Connecticut children's hospitals. TREC levels for children with CHD were compared with the general population. TREC levels and outcome measures, including hospitalization for infection, were compared. RESULTS: We enrolled 575 participants with CHD in the study. The median TREC level for newborns with CHD was lower than the general population (180.1 copies/µL vs 312.5 copies/µL; P < .01). patients with CHD requiring hospitalization for infection had lower median TREC levels than their counterparts (143.0 copies/µL vs 186.7 copies/µL; P < .01). The combination of prematurity and low TREC level had a strong relationship to hospitalization for infection (area under the receiver operative characteristic curve of 0.89). There was no association between TREC level and CHD severity. CONCLUSIONS: Newborns with CHD demonstrated lower TREC levels than the general population. Low TREC levels were associated with hospitalization for infection in preterm children with CHD. Study limitations include that this was a retrospective chart review. These findings may help to identify newborns with CHD at highest risk for infection, allowing for potential opportunities for intervention.

6.
Zhongguo Zhong Yao Za Zhi ; 44(9): 1960-1964, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31342727

RESUMO

Alpinia oxyphylla is mainly produced in Hainan,and also one of the four famous traditional Chinese medicines in South China with increasing importance in traditional Chinese medicine industry. Field surveys and literatures show that A. oxyphylla has widely used as a medicinal and edible plant,it is an important raw material for many Chinese patent medicines,health products and food,with a long history of artificial cultivation and application. The future development is prospected on health market. But A. oxyphylla industry has faced a lot of problems,including unreasonable planting layout,lack of good varieties,imperfect seed breeding system,low level of standardization,inconsistent quality of medicinal materials,low level of industry,and so on. The suggestions for sustainable development are listed below.First,it is essential to strengthen the research on the basis and application technology of A. oxyphylla,speed up the selection and breeding of improved varieties,and popularize standardized cultivation techniques. Secondly,it is important to strengthen the research on quality standards,improve the quality evaluation system of medicinal materials. Thirdly,it is necessary to take full advantage of the functional components to develop functional products with Hainan characteristics,find out the unique product characteristics of A. oxyphylla,build a famous brand and improve the product competitiveness in the market. It is also important to strengthen policy support and industrial supervision,promote the healthy and rapid development of A. oxyphylla industry.


Assuntos
Alpinia/química , Medicamentos de Ervas Chinesas/farmacologia , China , Medicina Tradicional Chinesa/tendências , Melhoramento Vegetal , Plantas Medicinais/química , Sementes
7.
Artigo em Inglês | MEDLINE | ID: mdl-31173404

RESUMO

Osteoporosis is one of the clinical complications of long-term treatment with glucocorticoids (GCs), characterized by systemic damage of bone mass and osteoblast dysfunction. Hydrogen sulfide was found to be involved in GCs-induced osteoblast dysfunction. Osteoblastic MC3T3-E1 cell and mitochondrial function were determined by cell viability, M-CSF level, and ALP activity and superoxide production, membrane potential, and ATP level, respectively. The purpose of this research was to explore the impact of NaHS on osteoblastic MC3T3-E1 cell function as well as on Sirt1 and PGC1α expression in dexamethasone (DEX)-treated osteoblast cells. DEX-treated MC3T3-E1 cells exhibited decreased cell viability and ALP activity, as well as increased M-CSF level; all these changes were dramatically attenuated by NaHS. DEX-treated cells also displayed mitochondrial dysfunction, namely decreased mitochondrial membrane potential and ATP generation and increased superoxide generation, which were partly reversed by NaHS. We confirmed decreased Sirt1 and PGC1α protein expression in DEX-treated MC3T3-E1 cells by Western blot, which was also partly reversed by NaHS. Silencing of Sirt1 abrogated the protective effect of NaHS against DEX-induced cell damage and mitochondrial dysfunction. NaHS alleviates DEX-induced osteoblastic MC3T3-E1 cell injury by improving mitochondrial function.

8.
Fitoterapia ; : 104195, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31175953

RESUMO

We investigated the transdermal drug permeation enhancement properties and associated mechanisms of white mustard (Sinapis alba L.) seed volatile oil (SVO). Using gas chromatography-mass spectrometry, we showed that SVO was composed primarily of allylisothiocyanate and isothiocyanatocyclopropane. Compared with azone, SVO had better penetration-enhancing effects on three model drugs (5-Fluorouracil, Osthole, and Paeonol), with each having different oil-water partition coefficients. Histopathology showed that SVO did not induce skin irritation when the concentration was lower than 2% (v/v), and it induced less irritation than azone. According to attenuated total reflection-Fourier transform infrared spectroscopy and transmission electron microscopy, SVO induced skin lipid structural disorder and increased the distance between the stratum corneum, which is beneficial to the penetration of drugs. Cellular experiments showed that SVO inhibited Ca2+-ATPase activity, increased intracellular Ca2+ concentration, and changed the membrane potential in HaCaT cells, which promoted drug transfer into the skin. Our findings reveal that SVO is a safe and efficient natural product that has great potential as skin penetration enhancer.

9.
Angew Chem Int Ed Engl ; 58(32): 10941-10945, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31166076

RESUMO

A synergistic catalytic method combining photoredox catalysis, hydrogen-atom transfer, and proton-reduction catalysis for the dehydrogenative silylation of alkenes was developed. With this approach, a highly concise route to substituted allylsilanes has been achieved under very mild reaction conditions without using oxidants. This transformation features good to excellent yields, operational simplicity, and high atom economy. Based on control experiments, a possible reaction mechanism is proposed.

10.
Cell Cycle ; 18(14): 1560-1572, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31157588

RESUMO

Several lines of evidence suggest that circular RNAs (circRNAs) play important roles in oncogenesis and tumor progression. However, our knowledge of the role of circRNAs in gastric cancer (GC) remains limited. We investigated the possibility that circular RNA 0047905 (circRNA0047905) might act as a tumor promoter in the pathogenesis of gastric cancer by profiling miRNA expression in GC tissues and paired noncancerous mucosa tissues using miRNA microarrays. Next, a ceRNA network was constructed according to common miRNAs binding circRNAs and mRNAs. Mechanistically, we demonstrated that circRNA0047905 directly binds miR4516 and miR1227-5p, relieving suppression for targets SERPINB5 and MMP11. We observed that down-regulated circRNA0047905 expression in gastric cancer cells inhibited Akt/CREB signaling pathway activation. RNA scope in situ hybridization revealed expression of circRNA0047905 in GC. Our data suggest that circRNA0047905 is a promising target for GC diagnosis and therapy.

11.
J Colloid Interface Sci ; 553: 758-767, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31254873

RESUMO

Fast recombination of photo-generated carriers and limited photo-response have greatly hindered the development of TiO2-based photocatalysts. Herein, we present a ternary three-dimensionally ordered macroporous (3DOM) carbon dots (CDs)/Bi:TiO2 photocatalyst, which affords well-designed charge transmission and allows broad-spectrum absorption, thus delivering enhanced photocatalytic performance. The carbon dots act as effective electron extractors to accelerate the separation of electron-hole pairs, and pore engineering of the 3DOM Bi:TiO2 skeleton greatly promotes the response of light in the whole solar spectrum range. Impressively, the 3DOM CDs/Bi:TiO2 catalyst exhibits a greatly enhanced photocatalytic degradation performance toward phenol (92.7% in 2 h), and RhB (96.4% in 40 min) under full-spectra illumination, compared to the pristine 3DOM TiO2. This work provides a new design strategy for the optimization of carriers transmission pathway in high-quality and low-cost photocatalysts.

12.
Nature ; 570(7759): 91-95, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31118514

RESUMO

The development of two-dimensional (2D) materials has opened up possibilities for their application in electronics, optoelectronics and photovoltaics, because they can provide devices with smaller size, higher speed and additional functionalities compared with conventional silicon-based devices1. The ability to grow large, high-quality single crystals for 2D components-that is, conductors, semiconductors and insulators-is essential for the industrial application of 2D devices2-4. Atom-layered hexagonal boron nitride (hBN), with its excellent stability, flat surface and large bandgap, has been reported to be the best 2D insulator5-12. However, the size of 2D hBN single crystals is typically limited to less than one millimetre13-18, mainly because of difficulties in the growth of such crystals; these include excessive nucleation, which precludes growth from a single nucleus to large single crystals, and the threefold symmetry of the hBN lattice, which leads to antiparallel domains and twin boundaries on most substrates19. Here we report the epitaxial growth of a 100-square-centimetre single-crystal hBN monolayer on a low-symmetry Cu (110) vicinal surface, obtained by annealing an industrial copper foil. Structural characterizations and theoretical calculations indicate that epitaxial growth was achieved by the coupling of Cu <211> step edges with hBN zigzag edges, which breaks the equivalence of antiparallel hBN domains, enabling unidirectional domain alignment better than 99 per cent. The growth kinetics, unidirectional alignment and seamless stitching of the hBN domains are unambiguously demonstrated using centimetre- to atomic-scale characterization techniques. Our findings are expected to facilitate the wide application of 2D devices and lead to the epitaxial growth of broad non-centrosymmetric 2D materials, such as various transition-metal dichalcogenides20-23, to produce large single crystals.

13.
Bioorg Med Chem Lett ; 29(13): 1576-1579, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31078411

RESUMO

Basing on chromatographic separation techniques, fifteen aglycones (1-15), including two new anthraquinone aglycones (1, 2) and thirteen known compounds (3-15), were isolated from the small polar fraction of Cassia obtusefolia (petroleum ether extract). Structural elucidations were performed by 1D/2D NMR spectroscopy and mass spectrometry. The in vitro antioxidant and α-glucosidase inhibitory activities of these fifteen compounds were determined. Except compounds 12 (IC50 3.03 ±â€¯0.31 µg/mL, stronger than ascorbic acid, which IC50 was 6.48 ±â€¯2.30 µg/mL) and 13 (IC50 78.40 ±â€¯2.39 µg/mL), the free radical scavenging capacities of other compounds were weak. Compounds 4, 5, 6 and 13 exhibited inhibitory activities on α-glucosidase with IC50 values of 50.60 ±â€¯1.10, 22.57 ±â€¯0.07, 60.09 ±â€¯1.40, and 80.01 ±â€¯2.66 µg/mL separately, however, all the α-glucosidase inhibitory activities were weaker than positive control (acarbose).

14.
Biomed Pharmacother ; 116: 109005, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31136947

RESUMO

OBJECTIVE: High-Mobility Group Box 1 (HMGB1) promotes vascular injuries induced by limb Ischemia and Reperfusion (IR), but the molecular mechanisms are not well understood. This study aimed to investigate the role of Receptor for Advanced-Glycation End products (RAGE) in HMGB1-regulated inflammatory response and vascular injury in limb IR using the rat IR and cellular Hypoxia and Reoxygenation (HR) models. METHODS: We analyzed the vascular structure and elastic fiber deposition in rat femoral arteries by histological staining. We determined gene expression in vascular tissues and cells by quantitative RT-PCR, Western blotting and immunofluorescence; analyzed the protein levels in rat serum or cell supernatant by ELISA; and assessed protein interaction by co-immunoprecipitation. We used CCK-8 for analyzing cell viability, and assessed apoptosis by Hoechst staining and flow cytometry. RESULTS: RAGE inhibition by FPS-ZM1 significantly repressed rat vascular injury that was induced by limb IR treatment. HMGB1 and RAGE expression, P38, ERK1/2, P65 and IKBa phosphorylation, as well as HIF-1a, NLRP3, Caspase-1, TNF-a and IL-6 expression and P65 in nucleus, increased in femoral arteries of a rat IR model and HUVEC undergoing HR treatment, whereas all the factors except HMGB1 and RAGE were inhibited by FPS-ZM1 treatment. In addition, we found that HMGB1 binds with RAGE in HUVEC undergoing HR treatment, which was suppressed by FPS-ZM1. Finally, the apoptosis of HUVEC also increased by HR treatment, but repressed under FPS-ZM1 treatment. CONCLUSION: HMGB1 binds with RAGE to promote vascular inflammation and endothelial cell apoptosis, which mediates vascular injury during acute limb IR.

15.
Lancet Diabetes Endocrinol ; 7(7): 540-548, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31085143

RESUMO

BACKGROUND: Few studies have used nationally representative data to describe dietary trends and the related cardiometabolic mortality burden in China. Thus, we aimed to characterise the trends in disease-related dietary factors as well as their associated disease burden among Chinese adults from 1982 to 2012. METHODS: For this cross-sectional population-based study, we analysed a nationally representative sample of 204 802 adults aged 20 years or older, using data from the 1982, 1992, 2002, and 2010-12 China National Nutrition Surveys (CNNS). We did a comparative risk assessment, in which the effects of suboptimal intakes of 12 dietary factors, individually and collectively, on cardiometabolic mortality were estimated by calculating the population attributable fraction (PAF) to estimate the proportional reduction in cardiometabolic deaths that would occur if exposure to each dietary risk factor was reduced to an alternative optimal level. FINDINGS: The overall PAF of mortality from cardiovascular disease and type 2 diabetes that was associated with suboptimal dietary quality was 62·2% in 1982, 57·9% in 1992, 56·2% in 2002, and 51·0% in 2010-12, which accounted for 21·6% of total mortality in China in 1982, 16·6% in 1992, 17·6% in 2002, and 20·8% in 2010-12. The estimated number of cardiometabolic deaths associated with suboptimal dietary intakes was 1·07 million in 1982, 0·93 million in 1992, 1·18 million in 2002, and 1·51 million in 2010-12. Of all 12 dietary factors examined, high sodium intake (17·3%), low fruit consumption (11·5%), and low marine omega-3 fatty acids (9·7%) were associated with the largest numbers of estimated cardiometabolic deaths in 2010-12. INTERPRETATION: We observed an improvement in several dietary factors in China in the past few decades. However, current intakes of these dietary factors remain suboptimal. Poor diet quality is estimated to be associated with a substantial proportion of deaths from heart disease, stroke, and type 2 diabetes in China. FUNDING: Ministry of Health, China, and Ministry of Science and Technology, China.

16.
Sci Total Environ ; 681: 331-338, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31121397

RESUMO

The aryl organophosphate flame retardant triphenyl phosphate (TPhP) has been frequently detected in environment and biota, and the potential risks of TPhP to aquatic organisms have also been demonstrated. The degradation of TPhP by CoFe2O4 activated peroxymonosulfate (PMS) was studied in this work. At initial pH of 7.0, 10 µM TPhP could be removed by 99.5% with 0.25 g/L CoFe2O4 and 0.5 mM PMS after 6 min oxidation, indicating the excellent performance of CoFe2O4 activated PMS process on the treatment of TPhP. The influence of PMS and CoFe2O4 dosage, initial pH, humic acid (HA), and anions (Cl-, NO3-, and HCO3-) on TPhP degradation were investigated systematically. Results showed that the degradation of TPhP was enhanced with increasing PMS concentrations from 0.1 to 1 mM, while it reduced as CoFe2O4 dosage increased. TPhP degradation efficiencies depended on solution pH with neutral pH showing the optimum degradation conditions. Recycling experiment indicated that the CoFe2O4 nanoparticles (NPs) possessed high potential for reusability. The radical identification experiments were performed and SO4•- was confirmed as the dominant radicals in TPhP degradation, and activation mechanism of PMS by CoFe2O4 NPs was hence explained. Humic acids (HA) (2-20 mg/L) as the representative organic natural matter existing in environment inhibited TPhP removal. Anions including Cl-, NO3-, and HCO3- all reduced TPhP degradation. In addition, TPhP degradation products were identified by liquid chromatography-mass spectrometry, and the degradation pathways of TPhP were proposed accordingly.

17.
Wei Sheng Yan Jiu ; 48(2): 284-288, 2019 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-31133109

RESUMO

OBJECTIVE: A new method for the determination of 16 amino acids in Hulless barley which were planted in the Tibetan plateau of China was established by the amino acid analyzer(AAA), and the amino acid was graded. METHODS: The samples were subjected to hydrolysis by the hydrochloric acid solution containing 0. 05% thioglycolic acid, and were carried out by AAA and hydrolyzed amino acid column PH(4. 6 mm×60 mm, 3 µm). The external standard method was used for quantitative analysis. RESULTS: This hydrolysis pretreatment process could effectively prevent oxidation of methionine. The recoveries were 93. 2%-96. 7%, and the relative standard deviations were no more than 2. 9%(n=6). As the cereal-restricted amino acid, Hulless barley restricted amino acid lysine was the content of up to 0. 367 g/100 g, and the lysine score(AAS) was 62. 4, which was better than the corresponding scores of wheat, glutinous rice, corn and millet. CONCLUSION: The method is accurate, and has good repeatability which could meet the requirements for determination of 16 amino acids in Hulless barley.


Assuntos
Aminoácidos/análise , Hordeum/química , China , Hidrólise , Zea mays
18.
Wei Sheng Yan Jiu ; 48(3): 468-473, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31133136

RESUMO

OBJECTIVE: To establish a high performance liquid chromatography method with fluorescence detection for a variety of vitamin K and to assess the content of vitamin K in animal foods. METHODS: Animal foods were hydrolyzed by 0.2 g lipase and 0.1 g protease in pH 8 for 4 hours, extracted with isooctane followed by rotary evaporation and reconstitution. The mobile phase was 900 mL methanol and 100 mL tetrahydrofuran which contained 5 mmol glacial acetic acid, 11 mmol zinc chloride and 6 mmol anhydrous sodium acetate. The content of vitamin K_1, menaquinone-4(MK-4), and menaquinone-7(MK-7)were separated on Atlantis T3 column(4.6 mm×250 mm, 5 µm)by high-performance liquid chromatography. The fluorescence detector was set at a wavelength of 320 nm for excitation and 410.3 nm for emission. RESULTS: The linear range of the method was 0.01-0.40 µg/mL, and coefficient of determination was > 0.999. The spiked recoveries were 84.4%-124.2% with relative standard deviation was <6%(n=6). MK-4 was the main form of vitamin K in pork and chicken. The highest content of vitamin K_1 was found in beef, and MK-7 could be detected in aquatic products. CONCLUSION: The proposed method is successfully applied for the determination of vitamin K in animal foods. A variety of vitamin K are distributed differently in distinct animals.


Assuntos
Vitamina K/farmacologia , Ração Animal , Animais , Cromatografia Líquida de Alta Pressão
19.
Sensors (Basel) ; 19(7)2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30934719

RESUMO

Hypertension is one of the most common cardiovascular diseases, which will cause severe complications if not treated in a timely way. Early and accurate identification of hypertension is essential to prevent the condition from deteriorating further. As a kind of complex physiological state, hypertension is hard to characterize accurately. However, most existing hypertension identification methods usually extract features only from limited aspects such as the time-frequency domain or non-linear domain. It is difficult for them to characterize hypertension patterns comprehensively, which results in limited identification performance. Furthermore, existing methods can only determine whether the subjects suffer from hypertension, but they cannot give additional useful information about the patients' condition. For example, their classification results cannot explain why the subjects are hypertensive, which is not conducive to further analyzing the patient's condition. To this end, this paper proposes a novel hypertension identification method by integrating classification and association rule mining. Its core idea is to exploit the association relationship among multi-dimension features to distinguish hypertensive patients from normotensive subjects. In particular, the proposed method can not only identify hypertension accurately, but also generate a set of class association rules (CARs). The CARs are proved to be able to reflect the subject's physiological status. Experimental results based on a real dataset indicate that the proposed method outperforms two state-of-the-art methods and three common classifiers, and achieves 84.4%, 82.5% and 85.3% in terms of accuracy, precision and recall, respectively.


Assuntos
Leitos , Mineração de Dados/métodos , Hipertensão/patologia , Adulto , Idoso , Algoritmos , Balistocardiografia/instrumentação , Balistocardiografia/métodos , Feminino , Frequência Cardíaca/fisiologia , Humanos , Hipertensão/classificação , Masculino , Sistemas Microeletromecânicos , Pessoa de Meia-Idade , Análise de Ondaletas
20.
Opt Express ; 27(5): 6660-6671, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876246

RESUMO

Cavity-enhanced optical controlling is experimentally observed with a low-control laser power in a cavity-atom ensemble system. Here, the three-level atoms are coupled with two optical modes of a Fabry-Perot cavity, where a new theoretical model is developed to describe the effective three-wave mixing process between spin-wave and optical modes. By adjusting either temperature or cavity length, we demonstrate the precise frequency tuning of the hybrid optical-atomic resonances. When the doubly-resonant condition is satisfied, the probe laser can be easily modulated by a control laser. In addition, interesting non-Hermitian physics are predicted theoretically and demonstrated experimentally, and all-optical switching is also achieved. Such a doubly-resonant cavity-atom ensemble system without a specially designed cavity can be used for future applications, such as optical signal storage and microwave-to-optical frequency conversion.

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