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1.
Nutr Metab Cardiovasc Dis ; 34(5): 1245-1256, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38342721

RESUMO

BACKGROUND AND AIMS: Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease. The relationship between the trajectories of obesity indicators and incident NAFLD is unknown. Therefore, this study aims to explore the sex-specific association between the trajectories of obesity indicators and the incidence of NAFLD. METHODS AND RESULTS: In total, 9067 participants were recruited for this longitudinal study. Obesity indicators use body mass index (BMI) and waist circumference (WC). The trajectory of obesity indicators was analyzed using the growth mixture modeling. The multivariate logistic regression model was used to analyze the association between obesity indicators' trajectories and incident NAFLD. Over a median follow-up of 1.82 years, 1013 (11.74%) participants developed NAFLD. We identified BMI and WC change trajectories as the stable group, increasing group, and decreasing group. After adjusting for baseline level and other confounders, multivariate logistic regression analysis showed that compared with stable group of BMI, the increasing group, and decreasing group odds ratio and 95% confidence interval of NAFLD were 2.10 (1.06-4.15), and 0.25 (0.09-0.67) in men, and 1.82 (1.08-3.04) and 0.32 (0.16-0.64) in women. Compared with stable group of WC, the increasing group was 2.57 (1.39-4.74) in men, the increasing group, and decreasing group were 2.29 (1.70-3.10) and 0.28 (0.12-0.64) in women. Sensitivity analysis showed that the results were stable. CONCLUSION: The BMI and WC changing trajectories are significantly associated with the incidence of NAFLD in men and women. Populations of real-world health examinations can be categorized based on obesity indicator changes to prevent NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Masculino , Humanos , Feminino , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Circunferência da Cintura , Índice de Massa Corporal , Fatores de Risco , Estudos Longitudinais , Incidência , Obesidade/diagnóstico , Obesidade/epidemiologia , Obesidade/complicações
2.
Nutr Metab Cardiovasc Dis ; 34(6): 1456-1466, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508988

RESUMO

BACKGROUND AND AIMS: Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease, which lacks effective drug treatments. This study aimed to construct an eXtreme Gradient Boosting (XGBoost) prediction model to identify or evaluate potential NAFLD patients. METHODS AND RESULTS: We conducted a longitudinal study of 22,140 individuals from the Beijing Health Management Cohort. Variable filtering was performed using the least absolute shrinkage and selection operator. Random Over Sampling Examples was used to address imbalanced data. Next, the XGBoost model and the other three machine learning (ML) models were built using balanced data. Finally, the variable importance of the XGBoost model was ranked. Among four ML algorithms, we got that the XGBoost model outperformed the other models with the following results: accuracy of 0.835, sensitivity of 0.835, specificity of 0.834, Youden index of 0.669, precision of 0.831, recall of 0.835, F-1 score of 0.833, and an area under the curve of 0.914. The top five variables with the greatest impact on the onset of NAFLD were aspartate aminotransferase, cardiometabolic index, body mass index, alanine aminotransferase, and triglyceride-glucose index. CONCLUSION: The predictive model based on the XGBoost algorithm enables early prediction of the onset of NAFLD. Additionally, assessing variable importance provides valuable insights into the prevention and treatment of NAFLD.


Assuntos
Biomarcadores , Aprendizado de Máquina , Hepatopatia Gordurosa não Alcoólica , Valor Preditivo dos Testes , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/sangue , Estudos Longitudinais , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Medição de Risco , Biomarcadores/sangue , Pequim/epidemiologia , Prognóstico , Reprodutibilidade dos Testes , Técnicas de Apoio para a Decisão , Fatores de Risco , Diagnóstico por Computador
3.
Nutr Metab Cardiovasc Dis ; 34(2): 506-514, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176959

RESUMO

BACKGROUND AND AIM: Previous studies have demonstrated an association between SUA and dyslipidemia. This study aims to explore the temporal relationship between SUA and dyslipidemia. METHODS AND RESULTS: Based on the Beijing Health Management Cohort conducted from 2013 to 2018, the data of a physical examination population was collected, including a total of 6630 study subjects. Cross-lagged panel analysis was employed to examine the temporal relationship between elevated SUA levels and dyslipidemia, indicated by either elevated TG or decreased HDL-C. The path coefficient and the 95 % CI from baseline TG to follow-up SUA were as follows: in the general population, men, women, and people with BMI ≥25 kg/m2were 0.027 (0.008-0.045), 0.024 (0.001-0.048), 0.032 (0.001-0.063) and 0.033 (0.006-0.059) (P < 0.05); however, the path coefficient from baseline SUA to follow-up TG and the 95 % CI were not statistically significant. Furthermore, the path coefficients and 95 % CIs between elevated SUA and decreased HDL-C were not statistically significant, both in the general population and in populations stratified by gender and BMI. CONCLUSIONS: We found a temporal relationship from elevated TG to elevated SUA in the general population and the populations stratified by gender and BMI (≥25 kg/m2). However, we did not observe a reverse relationship from elevated SUA to elevated TG. Additionally, we did not find a temporal relationship between decreased HDL-C and elevated SUA in both the general population and the stratified populations.


Assuntos
Dislipidemias , Ácido Úrico , Masculino , Humanos , Feminino , Estudos de Coortes , Pequim/epidemiologia , Dislipidemias/diagnóstico , Dislipidemias/epidemiologia , Estudos Transversais
4.
BMC Ophthalmol ; 24(1): 13, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191381

RESUMO

PURPOSE: To characterize the in vivo corneal epithelial thickness (CET) remodeling profile in a population of eyes after small incision lenticule intrastromal keratoplasty (SMI-LIKE) for hyperopia. METHODS: The CET profile was measured by RTVue-100 Fourier-domain OCT system across the central 6-mm diameter of the cornea of 17 eyes from 12 subjects (five males and seven females) who accepted corneal stromal lens implantation surgery for correcting hyperopia. The CET were measured at positions with a radius of 0-1.0 mm, 1.0-2.5 mm (divided into eight quadrants) and 2.5-3.0 mm (divided into eight quadrants) from the corneal center. Corneal maximum simulated keratometry (Km) was measured by Pentacam HR anterior segment analyzer to analyze CET changes. The examination data of subjects were collected in four time periods, which were preoperative, short-term postoperative (one week after surgery), mid-term postoperative (the last review within 3-6 months after surgery), and long-term postoperative (the last review over 1-2.5 years after surgery). The changes of CET were compared and analyzed in the four time periods. RESULTS: Mean CET in 0-1.0 mm, 1.0-2.5 mm and 2.5-3.0 mm of the cornea decreased in one week after surgery, respectively, as compared to CET in the preoperative period, which turned from 55.06 ± 0.82 µm、54.42 ± 0.75 µm、53.46 ± 0.60 µm to 51.18 ± 1.05 µm (P = 0.005), 49.38 ± 0.70 µm (P = 0.000), 51.29 ± 0.59 µm (P = 0.025). In the mid-term postoperative period, mean CET in 0-1.0 mm and 1.0-2.5 mm areas kept thinner than mean CET in the preoperative period, CET in 0-1.0 mm is 50.59 ± 0.76 µm (P = 0.000),CET in 1.0-2.5 mm is 50.23 ± 0.57 µm (P = 0.000), while mean CET in 2.5-3.0 mm area recovered to the same thickness as the preoperative level, which is 54.36 ± 0.66 µm (P = 1.000), until the long-term period, CET stabilized in the above doughnut pattern. CONCLUSIONS: After stromal lenticule implantation for hyperopia, CET showed a remodeled form of thinning in the 0-2.5 mm area and thickening in the 2.5-3.0 mm area, and remained stable within one year after surgery.


Assuntos
Transplante de Córnea , Hiperopia , Feminino , Masculino , Humanos , Hiperopia/cirurgia , Tomografia de Coerência Óptica , Córnea , Substância Própria/cirurgia
5.
Int J Biometeorol ; 68(6): 1073-1079, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38438698

RESUMO

As a significant sector within the tourism industry, desert tourism has developed rapidly in recent years, contributing significantly to local economic development. On the other hand, desert tourism is constantly influenced by the desert climate, characterized by high temperatures, aridity, and dust events. This study examines and analyzes the impact of dust events on the Holiday Climate Index (HCI) using an improved methodology. It incorporates comprehensive meteorological data including temperature, relative humidity, cloud cover, precipitation, wind speed and dust events of Tazhong, located in the heart of the Taklimakan Desert. The results indicate that the maximum mean monthly HCI dips from an ideal level (91) to a very good level (73), the minimum dips from good level (66) to a marginal level (47), and the annual comfortable days (HCI ≥ 80) decrease from 180.5 to 95.3 after considering the impacts of dust events. The corrective HCI indicates that autumn, especially October, offers relatively comfortable climatic conditions for tourism, with the mean monthly comfortable days reach 20.1. These findings can better guide desert tourism activities and also demonstrate that the impact of dust weather on tourism activities cannot be ignored.


Assuntos
Clima Desértico , Poeira , Férias e Feriados , Poeira/análise , China , Turismo
6.
Environ Sci Technol ; 57(18): 7174-7184, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37079659

RESUMO

Desert carbon sequestration plays an active role in promoting carbon neutralization. However, the current understanding of the effect of hydrothermal interactions and soil properties on desert carbon sequestration after precipitation remains unclear. Based on the experiment in the hinterland of the Taklimakan Desert, we found that the heavy precipitation will accelerate the weakening of abiotic carbon sequestration in deserts under the background of global warming and intensified water cycle. The high soil moisture can significantly stimulate sand to release CO2 at an incredible speed by rapidly increasing microbial activity and organic matter diffusion. At this time, the CO2 flux in the shifting sand was synergistically affected by soil temperature and soil moisture. As far as soil properties are concerned, with less organic carbon substrate and stronger soil alkalinity, the carbon sequestration of shifting sand is gradually highlighted and strengthened at low temperature. On the contrary, the carbon sequestration of shifting sand is gradually weakened. Our study provides a new way to assess the contribution of desert to the global carbon cycle and improve the accuracy and scope of application.


Assuntos
Sequestro de Carbono , Ecossistema , Clima Desértico , Dióxido de Carbono , Solo/química , Carbono , China
7.
J Gastroenterol Hepatol ; 38(12): 2061-2069, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37642537

RESUMO

BACKGROUND AND AIM: Although an association between skeletal muscle mass index and nonalcoholic fatty liver disease (NAFLD) has previously been demonstrated, the causal direction remains unclear. Herein, we investigated the directional association between NAFLD and the serum creatinine-to-body weight ratio (sCr/bw), a surrogate marker of the muscle mass index, using longitudinal data. METHODS: We recruited 9662 participants in 2017 and performed follow-up over 4 years. We evaluated whether sCr/bw was related to NAFLD development (Analysis I) and whether NAFLD was associated with a low sCr/bw incidence (Analysis II) using logistic regression models. Furthermore, a random intercept cross-lagged panel model was applied to evaluate the bidirectional association between sCr/bw ratio and NAFLD (Analysis III). RESULTS: Analysis I demonstrated an association between sCr/bw and incident NAFLD (odds ratio [OR] = 0.160, 95% confidence interval [CI]:0.107-0.232). Analysis II indicated a relationship between NAFLD and subsequent low sCr/bw ratio (OR = 1.524, 95% CI: 1.258-1.846). Analysis III indicated that the standard regression coefficient from sCr/bw to subsequent hepatic steatosis (HS) was -0.053 for ßsCr/bw2017 â†’ HS2019 and -0.060 for ßsCr/bw2019 â†’ HS2021 and the coefficient from HS to subsequent sCr/bw was -0.093 for ßHS2017 â†’ sCr/bw2019 and -0.112 for ßHS2019 â†’ sCr/bw2021 (all P < 0.05). CONCLUSIONS: This study indicated mutual causality between sCr/bw and NAFLD. Considering that sCr/bw is a surrogate marker of muscle mass index, the findings emphasize that NAFLD and low muscle mass form a vicious cycle, which should be taken seriously in clinical practice.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/etiologia , Creatinina , Músculo Esquelético , Biomarcadores , Peso Corporal
8.
Nutr Metab Cardiovasc Dis ; 33(7): 1339-1348, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37248143

RESUMO

BACKGROUND AND AIMS: Serum uric acid to creatinine ratio (SUA/Cr) may be associated with metabolic syndrome (MS). Here, we investigated the correlation between SUA/Cr and MS in Chinese residents aged ≥ 45 years. METHODS AND RESULTS: Data were obtained from the 2015 China Health and Retirement Longitudinal Study (CHARLS) database. MS was diagnosed using the Chinese Diabetes Society 2017 criteria. We grouped the population according to SUA/Cr quartiles and compared the index differences between groups. We used spearman correlation analysis and binary logistic regression. The possible dose-response association of SUA/Cr with MS were analyzed using restricted cubic spline model. Of 12,946 included participants, 3370 (26.0%) had MS, and 1900 (56.4%) were female. After adjusting for multiple confounders, binary logistic regression analysis showed that compared with Quartile 1, the odds ratio (95% confidence interval) of the MS risk was 1.29 (1.09-1.52), 1.47 (1.25-1.74), and 1.80 (1.53-2.12) in Quartiles 2, 3, and 4, respectively. The restricted cubic spline model indicated a significant nonlinear dose-response association (Poverall < 0.001, Pnon-linearity = 0.029) between SUA/Cr and strength of MS prevalence association; MS risk began increasing when SUA/Cr > 6.22. CONCLUSIONS: A significant positive correlation existed between SUA/Cr and MS risk in Chinese individuals aged ≥ 45 years, which may be a new predictive marker for MS risk.


Assuntos
Síndrome Metabólica , Pessoa de Meia-Idade , Humanos , Idoso , Feminino , Masculino , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , Ácido Úrico , Estudos Longitudinais , Aposentadoria , Creatinina , China/epidemiologia , Fatores de Risco
9.
Nutr Metab Cardiovasc Dis ; 33(5): 967-977, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36958974

RESUMO

BACKGROUND AND AIM: Conflicting results suggest a link between serum uric acid and diabetes and previous studies ignored the effect of continuous exposure of serum uric acid on diabetes risk. This study aims to characterize hyperuricemia trajectories in middle-aged adults and to examine its potential impact on diabetes risk, considering the role of obesity, dyslipidemia, and hypertension. METHODS AND RESULTS: The cohort included 9192 participants who were free of diabetes before 2013. The hyperuricemia trajectories during 2009-2013 were identified by latent class growth models. Incident diabetes during 2014-2018 was used as the outcome. Modified Poisson regression models were used to assess the association of trajectories with diabetes. Furthermore, marginal structural models were used to estimate the mediating effects of the relationship between hyperuricemia trajectories and diabetes. We identified three discrete hyperuricemia trajectories: high-increasing (n = 5794), moderate-stable (n = 2049), and low-stable (n = 1349). During 5 years of follow-up, we documented 379 incident diabetes cases. Compared with the low-stable pattern, the high-increasing pattern had a higher risk of developing diabetes (RR, 1.42; 95% CI: 1.09-1.84). In addition, the percentages of total effect between the high-increasing hyperuricemia pattern and diabetes mediated by obesity, dyslipidemia, and hypertension were 24.41%, 18.26%, and 6.29%. However, the moderate-stable pattern was not associated with an increased risk of diabetes. CONCLUSIONS: These results indicate that the high-increasing hyperuricemia trajectory is significantly associated with an increased risk of diabetes. Furthermore, obesity, dyslipidemia, and hypertension play mediating roles in the relationship between the high-increasing hyperuricemia pattern and increased diabetes risk.


Assuntos
Diabetes Mellitus , Dislipidemias , Hipertensão , Hiperuricemia , Adulto , Pessoa de Meia-Idade , Humanos , Fatores de Risco , Ácido Úrico , Estudos Prospectivos , Hiperuricemia/diagnóstico , Hiperuricemia/epidemiologia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Obesidade , Dislipidemias/diagnóstico , Dislipidemias/epidemiologia , Dislipidemias/complicações
10.
BMC Endocr Disord ; 22(1): 50, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35227230

RESUMO

BACKGROUND: High Blood Urea Nitrogen (BUN) and high Serum Creatinine (SCr) levels are risk factors for Coronary Artery Disease (CAD). However, the relationship between the Blood Urea Nitrogen to Creatinine (BUN/SCr) ratio (UCR) and the risk of CAD in patients living with new-onset diabetes is unclear. This study aimed to examine the relationship between blood UCR and the risk of CAD in patients living with new-onset type 2 diabetes mellitus (T2DM). METHODS: We analyzed the data from the cohort of 12,299 patients living with type 2 diabetes mellitus. Primary endpoints were the events of CAD. The ANOVA test (continuous indicators) and χ2 test (categorical indicators) were used to assess the differences of baseline characteristics across the groups of UCR. In order to understand the correlation between variables, we performed correlation analysis on variables that have significant differences between CAD group and non-CAD group. Multivariate-adjusted Cox proportional hazard regression models were applied to estimate the association of the blood UCR with the risk of CAD in patients living with T2DM. The Kaplan-Meier survival function plotting and the log-rank test were used to evaluate the event-free survival according to the groups of UCR. The restricted cubic spline model was used to show the adjusted association between blood UCR and risk of CAD in patients living with T2DM. RESULTS: During a median follow-up of 2.66 years, 1173 CAD were recorded with an event rate of 28.49 events per 1000 person-years. In multivariate-adjusted Cox regression models, elevated blood urea nitrogen to creatinine ratio (UCR) was associated with higher risk of CAD in patients living with T2DM [hazard ratio (HR), 1.782; 95% confidence interval (CI), 1.237-2.567]. The Kaplan-Meier survival curves indicated that the high group of UCR tended to have a lower event-free survival than the low group and medium group. There was a nonlinear trend toward increasing risk of CAD across the groups of UCR. And cubic spline function graph suggested that the influence of UCR level on HR for CAD increased significantly at UCR levels above 6.67. CONCLUSIONS: An elevated UCR was significantly associated with an increased risk for CAD in patients living with T2DM.


Assuntos
Nitrogênio da Ureia Sanguínea , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/epidemiologia , Creatinina/sangue , Diabetes Mellitus Tipo 2/complicações , Adulto , Idoso , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco , Análise de Sobrevida
11.
Appl Opt ; 61(22): 6653-6657, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36255891

RESUMO

The electric double layer (EDL) was formed at the interface of the electrode and liquid and has been widely used in a series of applications, ranging from batteries to biosensors, based on the electrical property changes. In this paper, we demonstrate a simple microfiber phase shifter based on the Pockels effect of liquid in the electric double layer. By constructing an EDL around the microfiber, the phase shifter can be achieved. Furthermore, the effects of ion concentration and molecular polarity of liquids on this phase shifter were studied. The fiber electric double-layer platform has the advantages of low voltage modulation and simple fabrication, which has the potential for use in wearable sensing devices, biopotential detection, and biomolecule detection.


Assuntos
Técnicas Biossensoriais , Eletricidade , Eletrodos , Fontes de Energia Elétrica
12.
BMC Public Health ; 22(1): 2306, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494707

RESUMO

BACKGROUND: Health interventions can delay or prevent the occurrence and development of diabetes. Dynamic nomogram and risk score (RS) models were developed to predict the probability of developing type 2 diabetes mellitus (T2DM) and identify high-risk groups. METHODS: Participants (n = 44,852) from the Beijing Physical Examination Center were followed up for 11 years (2006-2017); the mean follow-up time was 4.06 ± 2.09 years. Multivariable Cox regression was conducted in the training cohort to identify risk factors associated with T2DM and develop dynamic nomogram and RS models using weighted estimators corresponding to each covariate derived from the fitted Cox regression coefficients and variance estimates, and then undergone internal validation and sensitivity analysis. The concordance index (C-index) was used to assess the accuracy and reliability of the model. RESULTS: Of the 44,852 individuals at baseline, 2,912 were diagnosed with T2DM during the follow-up period, and the incidence density rate per 1,000 person-years was 16.00. Multivariate analysis indicated that male sex (P < 0.001), older age (P < 0.001), high body mass index (BMI, P < 0.05), high fasting plasma glucose (FPG, P < 0.001), hypertension (P = 0.015), dyslipidaemia (P < 0.001), and low serum creatinine (sCr, P < 0.05) at presentation were risk factors for T2DM. The dynamic nomogram achieved a high C-index of 0.909 in the training set and 0.905 in the validation set. A tenfold cross-validation estimated the area under the curve of the nomogram at 0.909 (95% confidence interval 0.897-0.920). Moreover, the dynamic nomogram and RS model exhibited acceptable discrimination and clinical usefulness in subgroup and sensitivity analyses. CONCLUSIONS: The T2DM dynamic nomogram and RS models offer clinicians and others who conduct physical examinations, respectively, simple-to-use tools to assess the risk of developing T2DM in the urban Chinese current or retired employees.


Assuntos
Diabetes Mellitus Tipo 2 , Masculino , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Fatores de Risco , Nomogramas
13.
Spinal Cord ; 60(3): 199-209, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34172926

RESUMO

STUDY DESIGN: This is a cross-sectional descriptive study. OBJECTIVES: To quantify differences in hand muscle morphology between persons with cervical spinal cord injury (SCI) and uninjured adults. SETTING: The study was performed at the Guangdong Work Injury Rehabilitation Hospital. METHODS: We quantified hand muscle cross-sectional area (CSA), thickness, and echo intensity (EI) in 18 persons with subacute to chronic SCI and 23 controls using ultrasound imaging. RESULTS: Mean SCI abductor pollicis brevis (APB), abductor digiti minimi (ADM), and first dorsal interosseous (FDI) CSA were ~26%, 43%, and 37% smaller than the control means, the deficit in the APB being less than the ADM (P < 0.05). Muscle thickness was also smaller after SCI, but deficits in ADM (31%) and FDI (20%) thickness were less than the CSA deficits (P < 0.05). In five SCI persons, APB CSA and/or opponens pollicis (OP) thickness were normal despite complete motor paralysis. Mean longitudinal image EI was 40% higher in the OP and 15% higher in the flexor pollicis brevis (FPB) after SCI (P < 0.05), suggesting denervation-induced infiltration of fat and fibrous tissues. OP EI was related to OP thickness (r = -0.6, P = 0.007, n = 18). Mean axial image EI was 10% higher in the APB and ADM after SCI (P < 0.05). There were no significant correlations between muscle morphological properties and clinical features in the SCI participants. CONCLUSION: Our results indicate significant SCI atrophy and elevated EI that are muscle dependent.


Assuntos
Medula Cervical , Traumatismos da Medula Espinal , Adulto , Medula Cervical/diagnóstico por imagem , Eletromiografia/métodos , Mãos/diagnóstico por imagem , Mãos/fisiologia , Humanos , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/diagnóstico por imagem , Ultrassonografia
14.
Opt Express ; 29(12): 18305-18314, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34154089

RESUMO

A proposal toward the enhancement in the sensitivity of a fiber-based surface plasma resonance (SPR) refractive index (RI) sensor is explored experimentally using a Bessel-like beam as the input source. We splice a section of single-mode fiber and a section of multimode fiber to construct the Bessel-like beam, which contains a series of concentric rings for the consistency of the resonance angle configuration to improve the performance of the SPR sensor. We fabricate a dual-truncated-cone (DTC) structure of the fiber to excite and receive the SPR signals. The larger the number of concentric rings, the higher the sensitivity. The number of concentric ring is determined by the length of the multimode fiber. When the grinding angle of the DTC-sensing probe is 15° and the length of the multimode fiber is 500 µm, the maximum testing average sensitivity is 6908.3 nm/RIU, which is more sensitive than the previous SPR sensor introduced by the Gaussian beam as the input source in multimode fibers.

15.
Opt Express ; 29(18): 28864-28871, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34615007

RESUMO

The spider dragline silk (SDS) has a supercontraction characteristic, which may cause the axial length of the SDS to shrink up to 50% when the SDS is wet or the relative humidity is higher than 58% RH. In this manuscript, we employ the supercontraction characteristic of the SDS to measure relative humidity. We connect two sections of a single-mode fiber (SMF) and a section of multimode fiber (MMF) with a sandwich structure to fabricate a single-mode-multimode-single-mode (SMS) interferometer. Then we fix the SDS on two SMFs to configure a bow-shaped sensing unit. The increase of environmental humidity will cause the supercontraction of the SDS, which will cause the change of the SDS length. The excellent mechanical properties of the SDS will generate a strong pulling force and change the bending of the arch, whose interference spectrum will shift correspondingly. In this way, we may perform relative humidity sensing. In the relative humidity range of 58% RH to 100% RH, the average sensitivity is as high as 6.213 nm/% RH, higher than most fiber-based humidity sensors. Compared with the traditional sensing structure with humidity-sensitive materials, the proposed sensor improves the sensitivity with environmental friendliness. The results suggest that the SDS can be used for high-sensitivity humidity sensors, and its degradability and biocompatibility also have a vast development space in biochemical sensors.

16.
Opt Express ; 29(15): 22813-22822, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34614560

RESUMO

In this letter, a highly sensitive bending sensor based on an embedded multimode D-shaped long period fiber grating (EMD-LPFG) is proposed. The novel sensor is applied to carry out vector bending measurement. The proposed LPFG is fabricated by polishing on the prepared structure which is formed by periodically splicing between single mode fiber (SMF) and multimode fiber (MMF). Since the cross section of the embedded MMF is D-shaped, we named it EMD-LPFG. Due to the asymmetric modulation of the refractive index on the fiber by the CO2 laser, the sensor has the ability to distinguish the bending directions, and the MMFs provide higher bending response. The experimental transmission spectrum can match the simulation results well. The experimental results show that the average bending sensitivities in three orthogonal directions are 70.21 nm/m-1 (0°), 9.75 nm/m-1 (90°), -12.04 nm/m-1 (180°) and 9.98 nm/m-1 (270°), respectively. Meanwhile, the temperature sensitivity is 30 pm/°C in the range of 25 °C to 75 °C. According to the ultra-compact structure with the total length of 2.5 mm, high bending sensitivity and ability to distinguish the bending direction, the novel sensor has potential in bending measurement.

17.
Opt Lett ; 46(5): 1101-1104, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649667

RESUMO

In this Letter, we propose a microstructured in-fiber optofluidic surface-enhanced Raman spectroscopy (SERS) sensor for the initial inspection of uremia through the detection of unlabeled urea and creatinine. As a natural microfluidic device, microstructured hollow fiber has a special structure inside. Through chemical bonds, the SERS substrate can be modified and grown on the surface of the suspended core. Here, the silver nanoparticles (Ag NPs) are embedded on the poly diallyl dimethyl ammonium chloride-modified graphene oxide sheet to achieve the self-assembled SERS substrate. The reduced distance between Ag NPs can increase the strong hot spots that generate enhanced Raman signals. Therefore, it can effectively detect the Raman signal of unlabeled trace uremic toxin analytes (urea, creatinine) inside the optical fiber. The results show that under simulated biophysical conditions, the limit detection (LOD) for urea is 10-4M and the linearity is good, especially at the clinical conventional concentration range (2.5-6.5×10-3M). In addition, the online Raman detection of creatinine aqueous solution LOD is 10-6M, which also has good linearity. Significantly, this Letter provides a microstructured optofluidic in-fiber Raman sensor for the preliminary detection of uremia, which will have good development prospects in the field of clinical biomedicine.


Assuntos
Limite de Detecção , Fibras Ópticas , Análise Espectral Raman/instrumentação , Toxinas Biológicas/metabolismo , Uremia/metabolismo
18.
Opt Lett ; 46(10): 2497-2500, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33988618

RESUMO

A cheap, compact, and simply prepared all-fiber bidirectional optical modulator based on the Pockels effect of water and the band population effect was first, to the best of our knowledge, proposed and demonstrated. The transparent conductive oxide indium-tin-oxide (ITO) was coated on the surface of a nonadiabatic microfiber and first used as a modulating electrode on the microfiber. The device was realized by just submerging the microfiber in water. With supplying an electric field perpendicular to the interface between the microfiber and water, the refractive index was modulated in the electric double layer near the tapered region of the microfiber, under the Pockels effect of water. Subsequently, the interference spectrum was modulated. Meanwhile, the intensity of the light was modulated due to the band population effect in the space-charge layer. In this Letter, the proposed all-fiber optical modulator can realize simultaneous bidirectional modulation of the phase and intensity of output light. Experimentally, the maximum phase shift and the extinction ratio were 4.38 nm and 4.87 dB at 1550 nm, respectively. Significantly, the work used the Pockels effect of water and the band population effect to realize an all-fiber optical modulator, showing great potential in the optical phase modulators, optical switches, and electric field sensors.

19.
Nutr Metab Cardiovasc Dis ; 31(4): 1189-1199, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33549428

RESUMO

BACKGROUND AND AIMS: Although high serum uric acid (SUA) at baseline has been linked to increased risk for metabolic syndrome (MetS), the association of longitudinal SUA changes with MetS risk is unclear. We aimed to examine the effect of distinct SUA trajectories on new-onset MetS risk by sex in a Chinese cohort. METHODS AND RESULTS: A total of 2364 women and 2770 men who were free of MetS in 2013 were enrolled in this study and followed up to 2018. Group-based trajectory modeling was applied to identify SUA trajectories. Cox proportional hazards model was used to evaluate the association between SUA trajectory and new-onset MetS. The dose-response relationship between SUA trajectories and MetS risk was examined by treating trajectory groups as a continuous variable. During a median follow-up of 48.0 months, 311 (13.16%) women and 950 (34.30%) men developed MetS. SUA trajectories (2013-2018) were defined as four distinct patterns in both women and men: "low", "moderate", "moderate-high", and "high". Compared with "low" SUA trajectory, the adjusted hazard ratio for incident MetS among participants with "moderate", "moderate-high" and "high" trajectory was in a dose-response manner: 1.75 (95% CI: 1.08-2.82), 1.94 (95% CI: 1.20-3.14), and 3.05 (95% CI: 1.81-5.13), respectively, for women; 1.20 (95% CI: 0.97-1.49), 1.48 (95% CI: 1.19-1.85), and 1.66 (95% CI: 1.25-2.21), respectively, for men. CONCLUSIONS: Elevated SUA trajectories are associated with increased risk for new-onset MetS in women and men. Monitoring SUA trajectories may assist in identifying subpopulations at higher risk for MetS.


Assuntos
Hiperuricemia/sangue , Síndrome Metabólica/sangue , Ácido Úrico/sangue , Adulto , Biomarcadores/sangue , Fatores de Risco Cardiometabólico , China/epidemiologia , Feminino , Humanos , Hiperuricemia/diagnóstico , Hiperuricemia/epidemiologia , Estudos Longitudinais , Masculino , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores Sexuais , Fatores de Tempo , Regulação para Cima
20.
Appl Opt ; 60(22): 6659-6664, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34612910

RESUMO

In this paper, we present a microstructured optofluidic in-fiber Raman sensor for the detection of quinolone antibiotic residue in a water environment based on Ag surface-enhanced Raman scattering (SERS) substrate grown on the surface of the suspended core of micro-hollow optical fiber (MHF). Here, MHF has a special structure with a suspended core and a microchannel inside, which can become a natural in-fiber optofluidic device. Meanwhile, the self-assembled Ag SERS substrate can be grown on the suspended core's surface through chemical bonds, forming a microstructured optofluidic device with a Raman enhancement effect. Therefore, it can effectively detect the Raman signal of unlabeled trace quinolone antibiotic residue (ciprofloxacin and norfloxacin) inside the optical fiber. The results show that the ciprofloxacin and norfloxacin detection limits (LOD) are 10-10M and 10-11M, respectively. Compared with the maximum residue limit (3.01×10-7mol/L) stipulated by the European Union, the results are much lower, and an ideal quantitative relationship can be obtained within the detection range. Significantly, this study provides an in-fiber microstructured optofluidic Raman sensor for the label-free detection of quinolone antibiotic residue, which will have good development prospects in the field of antibiotic water pollution environmental detection.


Assuntos
Resíduos de Drogas/análise , Nanopartículas Metálicas , Fibras Ópticas , Quinolonas/análise , Análise Espectral Raman/instrumentação , Poluentes Químicos da Água/análise , Antibacterianos/análise , Ciprofloxacina/análise , Europa (Continente) , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Norfloxacino/análise , Valores de Referência , Prata
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