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1.
Dig Dis Sci ; 69(6): 2055-2073, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38573378

RESUMEN

BACKGROUND: Gastric cancer (GC) remains one of the most prevalent malignant tumors worldwide. At present, tumor-associated macrophages (TAMs) are essential in the progression, metastasis, and drug resistance of tumors. Therefore, TAMs can be a crucial target for tumor treatment. AIMS: We intended to investigate the TAM characteristics in GC and develop a risk signature based on TAM to predict the prognosis of GC patients. METHODS: The single-cell RNA sequencing (scRNA-seq) and bulk RNA-seq data were acquired from a publicly available database. We utilized the Seurat pipeline to process the scRNA-seq data and determine TAM cell types using marker genes. Univariate Cox regression analysis was utilized to examine TAM-related prognostic genes, and then we employed Lasso-Cox regression analysis, and Multivariate Cox regression analysis established a novel risk profile to forecast the clinical value of the model with a new nomogram combining risk profiles and clinicopathological characteristics. RESULTS: The current study employed scRNA-seq data to identify five TAM clusters in GC, among which four were significantly associated with GC prognosis. Accordingly, we further developed a TAM-related risk signature utilizing nine genes. After evaluation, our model accurately predicted the prognosis of gastric cancer. Generally, GC patients with low TAMS scores exhibited a more favorable prognosis, greater benefits from immunotherapy, and higher levels of immune cell infiltration. CONCLUSIONS: The prognosis of GC can be effectively predicted by TAM-based risk signatures, and the signature may provide a new perspective for comprehensively guiding clinical diagnosis, prediction, and immunotherapy for gastric cancer.


Asunto(s)
Inmunoterapia , Neoplasias Gástricas , Macrófagos Asociados a Tumores , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Neoplasias Gástricas/patología , Humanos , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/metabolismo , Pronóstico , Masculino , Femenino , Inmunoterapia/métodos , Persona de Mediana Edad , Nomogramas , Biomarcadores de Tumor/genética , Anciano , Microambiente Tumoral/inmunología , RNA-Seq , Análisis de la Célula Individual
2.
BMC Med Educ ; 24(1): 86, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267919

RESUMEN

BACKGROUND: Rain Classroom was one of the most popular online learning platforms in Chinese higher education during the pandemic. However, there is little research on user intention under the guidance of technology acceptance and unified theory (UTAUT). OBJECTIVE: This research aims to determine factors influencing students' behavioural intention to use Rain Classroom. METHODS: In this cross-sectional and correlational investigation, 1138 medical students from five medical universities in Guangxi Province, China, made up the sample. This study added self-efficacy (SE), motivation (MO), stress (ST), and anxiety (AN) to the UTAUT framework. This study modified the framework by excluding actual usage variables and focusing only on intention determinants. SPSS-26 and AMOS-26 were used to analyze the data. The structural equation modelling technique was chosen to confirm the hypotheses. RESULTS: Except for facilitating conditions (FC), all proposed factors, including performance expectancy (PE), effort expectancy (EE), social influence (SI), self-efficacy (SE), motivation (MO), anxiety (AN), and stress (ST), had a significant effect on students' behavioural intentions to use Rain Classroom. CONCLUSIONS: The research revealed that the proposed model, which was based on the UTAUT, is excellent at identifying the variables that influence students' behavioural intentions in the Rain Classroom. Higher education institutions can plan and implement productive classrooms.


Asunto(s)
Intención , Estudiantes de Medicina , Humanos , China , Estudios Transversales
3.
Opt Express ; 31(16): 25815-25828, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37710457

RESUMEN

The vertical profile of optical turbulence is a key factor in the performance design of astronomical telescopes and adaptive optics instruments. As site-testing campaigns are extremely expensive, the selection of appropriate spatial resolution data and estimation methods is extremely important. This study investigated the effect of using different methods (Dewan, HMNSP99, Thorpe method) to estimate the refractive index structure constant (C n2) using different resolution data (5 m, 25 m, ERA5 data) in Huaihua, Hunan. Compared with Dewan, HMNSP99 for estimating C n2 using 5 m and 25 m resolution data, the Thorpe method almost always shows the best performance, with RXY above 0.75 and lower RMSE and MRE between estimated and measured C n2. The results of C n2 estimation using HMNSP99 at different resolution data varied widely, indicating that HMNSP99 is more sensitive to the data resolution and the temperature gradient is more sensitive to the resolution. Using ERA5 data, the two methods of estimating C n2 using Dewan and HMNSP99 have close results. It indicates that the wind shear is the main factor when the spatial resolution of the data is reduced to a certain degree, and the contribution of temperature gradient is small in the high altitude turbulence.

4.
Pacing Clin Electrophysiol ; 46(9): 1035-1048, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37573146

RESUMEN

Transcatheter radiofrequency ablation has been widely introduced for the treatment of tachyarrhythmias. The demand for catheter ablation continues to grow rapidly as the level of recommendation for catheter ablation. Traditional catheter ablation is performed under the guidance of X-rays. X-rays can help display the heart contour and catheter position, but the radiobiological effects caused by ionizing radiation and the occupational injuries worn caused by medical staff wearing heavy protective equipment cannot be ignored. Three-dimensional mapping system and intracardiac echocardiography can provide detailed anatomical and electrical information during cardiac electrophysiological study and ablation procedure, and can also greatly reduce or avoid the use of X-rays. In recent years, fluoroless catheter ablation technique has been well demonstrated for most arrhythmic diseases. Several centers have reported performing procedures in a purposefully designed fluoroless electrophysiology catheterization laboratory (EP Lab) without fixed digital subtraction angiography equipment. In view of the lack of relevant standardized configurations and operating procedures, this expert task force has written this consensus statement in combination with relevant research and experience from China and abroad, with the aim of providing guidance for hospitals (institutions) and physicians intending to build a fluoroless cardiac EP Lab, implement relevant technologies, promote the standardized construction of the fluoroless cardiac EP Lab.


Asunto(s)
Ablación por Catéter , Técnicas Electrofisiológicas Cardíacas , Cirugía Asistida por Computador , Humanos , Electrofisiología Cardíaca , Ablación por Catéter/métodos , Técnicas Electrofisiológicas Cardíacas/métodos , Cirugía Asistida por Computador/métodos , Resultado del Tratamiento
5.
Heart Vessels ; 38(8): 1049-1055, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36928669

RESUMEN

Serum C-peptide exhibits various biological activities. The relationship between C-peptide and atrial cardiomyopathy remains unknown. We aimed to investigate the association between C-peptide level and atrial cardiomyopathy in nondiabetic adults. Our study enrolled 4578 participants without diagnosed diabetes from the Third National Health and Nutrition Examination Survey (NHANES III). Atrial cardiomyopathy was defined as a deep terminal negative P wave in V1 below - 100 µV (more negative), according to the electrocardiogram. The participants were categorized into low C-peptide (≤ 1.46 nmol/L) and high C-peptide (> 1.46 nmol/L) groups, according to the receiver operating characteristic analysis. Odds ratio (OR) and 95% confidence interval (CI) for the association between C-peptide level and atrial cardiomyopathy were generated using multivariate logistic regression analysis. The prevalence of atrial cardiomyopathy was higher in the high C-peptide group than in the low C-peptide group (5.62% vs. 2.31%, P < 0.001, respectively). Multivariate logistic regression analysis showed that participants in the high C-peptide group had a 3.60-fold (95% CI 1.81-6.99) higher risk of atrial cardiomyopathy than those in the low C-peptide group. Per standard deviation increase in C-peptide was linked to a 1.20-fold (95% CI 1.00-1.41) higher risk in atrial cardiomyopathy. High C-peptide level might be an independent risk factor for atrial cardiomyopathy in nondiabetic adults.


Asunto(s)
Fibrilación Atrial , Cardiomiopatías , Humanos , Adulto , Encuestas Nutricionales , Péptido C , Cardiomiopatías/diagnóstico , Cardiomiopatías/epidemiología , Factores de Riesgo
6.
Appl Opt ; 62(4): 1115-1122, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36821172

RESUMEN

Understanding turbulence in the free atmosphere is important for analyzing atmospheric pollution, forecasting weather, and light transmission. In this paper, we have tried to estimate the atmospheric refractive index structure constant C n2, the turbulent dissipation rate ε, and the turbulent diffusion coefficient K simultaneously during the experiment time over Lhasa, using the sounding data coupled with the Thorpe method. The result shows that the C n2 estimation gives a better performance with the correlation coefficients and the average relative error when compared with C n2 estimated by Dewan and HMNSP99. Besides this, the measured and estimated C n2, estimated ε, and K all show larger values in the troposphere, especially near the tropopause. It is worth noting that C n2 and ε are similar in terms of height distribution. These attempts at estimation all suggest that the Thorpe method can be used to estimate the intensity of turbulence in the free atmosphere over Lhasa.

7.
Opt Express ; 30(5): 7356-7371, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35299500

RESUMEN

Factors influencing atmospheric visibility (VIS) in coastal areas are more complex than those for inland and far oceans owing to the complex circulation and aerosol sources. This study analyzed the factors influencing VIS under sea-land breeze circulation (SLBC) for different external aerosol sources based on field survey data in southern Chinese coastal areas. First, SLBC characteristics observed during the experiment period showed that on SLBC days, sea breeze occurs more frequently (∼50%) than land breeze (∼27%), and the wind speed (WS) is generally small, with a mean sea and land breeze WSs of ∼2.18 m/s and ∼2.38 m/s, respectively. Then, analysis of factors influencing VIS was conducted for different land/sea breeze conditions and external aerosol source conditions indicated by the HYSPLIT4 model simulations. Results showed that the aerosol particle number concentration (PNC) and relative humidity (RH) both had negative correlations with VIS, while only very weak relationships between WS and VIS were found, possibly due to small WSs on SLBC days or because local aerosols were not pure marine aerosols. Further two-factor analysis of VIS showed that the power-law function relating VIS with PNC in each RH bin ranges from ∼-0.3 to ∼-1.5, and VIS exhibited sharper exponential decline with increasing PNC under high RH. A new method of retrieving aerosol-extinction hygroscopic growth factor (fext) with the measured VIS, RH, and PNC was developed to investigate the optical hygroscopic growth property of aerosols. Results show that aerosols in the study area have similar fext under different land/sea breeze and external aerosol source conditions; the deliquescence RH of aerosols is ∼60%, suggesting that mainly polluted marine aerosol was observed during experiments in this area.

8.
Pacing Clin Electrophysiol ; 45(6): 761-767, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35357706

RESUMEN

BACKGROUND: The risk of Cardiac Implantable Electronic Device (CIED) infection has been increasing in recent years. For pacemaker-dependent patients, a temporary pacemaker is needed before a new device can be implanted. The aim of this study is to evaluate the safety and efficacy of using a temporary pacing device with an externalized active fixation lead (bridge pacemaker) before a new device can be implanted in pacemaker-dependent patients with device infection. METHODS: All patients who were admitted to our cardiac center with CIED infection and in need of bridge pacemaker implantation from April 2013 to August 2020 were prospectively enrolled in this observational study. The medical records of all patients were collected and evaluated. All procedure-related complications were also collected. Long-term outcomes, including reinfection and death within 1 year after hospital discharge, were collected through telephone follow-ups. RESULTS: During the study period, 1050 patients underwent CIED extraction, of which 312 pacemaker-dependent patients underwent bridge pacemaker implantation. The mean age of the extracted leads was 44 ± 38.7 months. The bridge pacemakers were in use for a mean duration of 6 days. Nine patients developed procedure-related complications including pericardial tamponade, pneumothorax, peripheral venous thrombosis, and pulmonary embolism. Three patients developed complications that were related to their bridge pacemakers, including lead dislodgement, over-sensing and elevated pacing threshold. During the 1-year follow-up, it was found that four patients had developed CIED reinfection and three patients had died due to cardiac-related reasons. CONCLUSIONS: A bridge pacemaker with an externalized active fixation lead is safe and efficacious for pacemaker-dependent patients with device infection.


Asunto(s)
Desfibriladores Implantables , Marcapaso Artificial , Niño , Preescolar , Desfibriladores Implantables/efectos adversos , Remoción de Dispositivos , Humanos , Lactante , Alta del Paciente , Reinfección , Estudios Retrospectivos , Resultado del Tratamiento
9.
Appl Opt ; 61(33): 9762-9772, 2022 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-36606804

RESUMEN

We verified the feasibility of an alternative solution to generate temperature and pressure profiles with the U.S. standard atmosphere model (USSA-76). We simultaneously integrated this model with conventional meteorological parameters measured by a weather station in the course of estimating the refractive index structure constant (C n2). Moreover, a continuous-time-series estimation method of the refractive index structure constant was established within the marine atmospheric boundary layer (ABL) based on wind data obtained from a coherent Doppler wind lidar (CDWL). We also analyzed the optical turbulence characteristics induced by wind shear during the conducted experiment. Laminated and patchy stratified turbulences, which affect the performance of imaging and light transmission systems, were found within the marine ABL. Additionally, the relationship between the ABL and all atmospheric optical turbulence factors shows that the ratio of marine ABL in the entire layer differs from that reported in previous studies. Moreover, the influence of thermal turbulence factors within the marine ABL was less than that of the entire layer in our case. We report a real-time C n2 estimation method based on a CDWL. The characteristics of the marine ABL C n2 constitute a reference for optoelectronic applications.

10.
Int J Clin Pract ; 2022: 9177545, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35685607

RESUMEN

Objectives: The collateral circulation near the cerebral artery occlusion can contribute to the relief of the symptoms and signs of stroke. Genetic factors play a decisive role in the difference in collateral circulation. Survivin, encoded by the baculoviral inhibitor of apoptosis (IAP) repeat-containing 5 gene (BIRC5), plays an important role in maintaining long-term endothelial integrity and homeostasis and as an angiogenic factor in the treatment of vascular diseases. We hypothesized that genetic variations in the BIRC5 gene may contribute to severity by influencing the collateral circulation. This study aimed at examining how the polymorphism of the BIRC5 gene correlated with the collateral circulation and severity of large artery atherosclerotic stroke. Methods: This study enrolled 428 patients with large artery atherosclerotic stroke. There are no statistical differences in age, sex, social behavior, such as smoking and drinking, between the groups classified by the collateral circulation and by the severity of stroke (P > 0.01). Direct sequencing was performed for the genotyping of single nucleotide polymorphism (SNP) of BIRC5 (rs2071214). The enrolled patients were divided into several subgroups based on the collateral flow grading system from the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR), the results of the National Institutes of Health Stroke Survey (NIHSS) (6 as a threshold), and the score of the modified Rankin scale (mRS) (for the prediction of prognosis, 2 as a threshold). Differences among subgroups were identified through logistic regression. Results: The analysis of collateral circulation revealed the significant correlation of SNP of rs2071214 with the development of poor collateral circulation of large artery atherosclerotic stroke in the additive model (GG vs. AA, odds ratio (OR) = 3.592, 95% confidence interval (CI) = 1.410-9.150, and P=0.007) and the recessive model (GG vs. AA/GA, OR = 3.313, 95% CI = 1.420-7.727, and P=0.006). The analysis of stroke severity exposed the significant role of the SNP of rs2071214 in increasing stroke severity in the dominant model (GA/GG vs. AA, OR = 1.658, 95% CI = 1.017-2.703, and P=0.043) and the additive model (GA vs. AA, OR = 1.717, 95% CI = 1.021-2.888, and P=0.042). However, the analysis of the short-term outcome indicated that three genetic models were not associated with short-term outcomes in the additive model (GA vs. AA, P=0.815, GG vs. AA, and P=0.336), the dominant model (GA/GG vs. AA and P=0.589), and the recessive model (GG vs. AA/GA and P=0.342). Conclusion: Our findings identified the SNP of rs2071214 of the BIRC5 gene as a risk factor for the poor compensatory ability of collateral circulation and a predictor of stroke severity in large artery atherosclerotic stroke, which suggested that the SNP of rs2071214 can serve as an innovative therapeutic target for patients with acute ischemic stroke.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Arterias , Circulación Colateral , Humanos , Polimorfismo de Nucleótido Simple/genética , Accidente Cerebrovascular/genética , Survivin/genética
11.
BMC Pulm Med ; 22(1): 259, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35768814

RESUMEN

BACKGROUND: The expression profiles and molecular mechanisms of CXC chemokine receptors (CXCRs) in Lung adenocarcinoma (LUAD) have been extensively explored. However, the comprehensive prognostic values of CXCR members in LUAD have not yet been clearly identified. METHODS: Multiple available datasets, including Oncomine datasets, the cancer genome atlas (TCGA), HPA platform, GeneMANIA platform, DAVID platform and the tumor immune estimation resource (TIMER) were used to detect the expression of CXCRs in LUAD, as well as elucidate the significance and value of novel CXCRs-associated genes and signaling pathways in LUAD. RESULTS: The mRNA and/or protein expression of CXCR1, CXCR2, CXCR3, CXCR4, CXCR5 and CXCR6 displayed predominantly decreased in LUAD tissues as compared to normal tissues. On the contrary, compared with the normal tissues, the expression of CXCR7 was significantly increased in LUAD tissues. Subsequently, we constructed a network including CXCR family members and their 20 related genes, and the related GO functions assay showed that CXCRs connected with these genes participated in the process of LUAD through several signal pathways including Chemokine signaling pathway, Cytokine-cytokine receptor interaction and Neuroactive ligand-receptor interaction. TCGA and Timer platform revealed that the mRNA expression of CXCR family members was significantly related to individual cancer stages, cancer subtypes, patient's gender and the immune infiltration level. Finally, survival analysis showed that low mRNA expression levels of CXCR2 (HR = 0.661, and Log-rank P = 1.90e-02), CXCR3 (HR = 0.674, and Log-rank P = 1.00e-02), CXCR4 (HR = 0.65, and Log-rank P = 5.01e-03), CXCR5 (HR = 0.608, and Log-rank P = 4.80e-03) and CXCR6 (HR = 0.622, and Log-rank P = 1.85e-03) were significantly associated with shorter overall survival (OS), whereas high CXCR7 mRNA expression (HR = 1.604, and Log-rank P = 4.27e-03) was extremely related with shorter OS in patients. CONCLUSION: Our findings from public databases provided a unique insight into expression characteristics and prognostic values of CXCR members in LUAD, which would be benefit for the understanding of pathogenesis, diagnosis, prognosis prediction and targeted treatment in LUAD.


Asunto(s)
Adenocarcinoma del Pulmón , Adenocarcinoma , Neoplasias Pulmonares , Adenocarcinoma/patología , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Humanos , Neoplasias Pulmonares/patología , Pronóstico , ARN Mensajero/genética , ARN Mensajero/metabolismo
12.
J Cardiovasc Electrophysiol ; 32(11): 3051-3056, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34487387

RESUMEN

INTRODUCTION: The incidence of cardiac implantable electronic device (CIED) infections is increasing. Complete device and lead removal are recommended for all patients with definite CIED system infection. In patients with pacemaker dependency, temporary pacing before reimplantation is necessary. In this study, temporary pacing using active fixation leads (TPAFL) was evaluated. METHODS: We reviewed data from consecutive patients implanted with TPAFL after transvenous lead extraction at our center between November 2014 and October 2020. RESULTS: TPAFL were placed in 334 patients. The mean age was 64.5 ± 16.4 years and 76.3% were males. Two hundred and forty (72%) were treated due to local pocket infection and 94 (28%) systemic infection. The indication for temporary pacing was sick sinus syndrome in 135 (40.4%) patients and complete or high-grade atrioventricular (AV) block in 199 (59.6%) patients. The most common access site for lead implantation was the ipsilateral subclavian or axillary vein (78.9%). A new permanent CIED was reimplanted at 10.3 ± 9.2 days (median 10, range: 2-70) after implantation of the temporary pacing. There were five (1.5%) adverse events related to the temporary pacing during hospitalization. The median follow-up duration was 23.1 months (interquartile range [IQR], 7.2-43.4 months). Only one patient (0.3%) developed recurrent CIED infection. CONCLUSION: TPAFL is safe and effective in pacemaker-dependent patients after infected CIED removal. The rate of temporary pacing-related complications, including lead dislodgment and reinfection of CIED is relatively low.


Asunto(s)
Desfibriladores Implantables , Marcapaso Artificial , Anciano , Anciano de 80 o más Años , Desfibriladores Implantables/efectos adversos , Remoción de Dispositivos/efectos adversos , Electrónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Marcapaso Artificial/efectos adversos , Resultado del Tratamiento
13.
Echocardiography ; 38(9): 1552-1557, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34510520

RESUMEN

BACKGROUND: Transesophageal echocardiography (TEE) is commonly used during cardiothoracic procedures. TEE has also become standard during transvenous lead extraction (TLE) procedures, but its effect and role have not been optimally defined. The goal of this study is to identify how TEE was used during TLE at our institute and review its utility. METHODS: We retrospectively reviewed high-risk patients undergoing TLE, for whom more complications during extraction procedures, from June 2012 to September 2020. The patients were divided into TEE group and non-TEE group according to real-time TEE monitoring. We compared the rate of procedural success, complications between two groups and concluded the clinical utility of TEE during TLE. RESULTS: A total of 195 patients were included (105 in TEE group vs 90 in non-TEE group), the rate of procedure success (97.8% vs 96.5%, p = 0.41) and complications during extraction (8.6% vs 12.2%, p = 0.40, major complication 5.7% vs 12.2%, p = 0.11, minor complication 2.9% vs 0%, p = 0.30) were comparable. In TEE group, 12 patients (11.4%) received following benefits: altering surgical plans, guiding subsequent therapy strategies, and rapidly diagnosing complications, moreover no complications occurred from TEE. CONCLUSIONS: This study demonstrates that real-time monitoring by TEE cannot change the rate of procedural success and complication during TLE; however, TEE provides valuable information to instruct clinical therapy and improves the safety of TLE.


Asunto(s)
Desfibriladores Implantables , Ecocardiografía Transesofágica , Desfibriladores Implantables/efectos adversos , Remoción de Dispositivos , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
14.
Opt Express ; 28(4): 4571-4586, 2020 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-32121691

RESUMEN

The vertical distributions of optical turbulence (C n2 profiles) are a major factor in defining the capabilities of ground-based telescopes and interferometers. As site-testing campaigns are extremely expensive and instruments only provide the local atmospheric parameter, atmospheric modeling might represent an advance prediction result in astronomical sites. The key meteorological parameters and the integrated astroclimatic parameters (Fried parameter r0, seeing ɛ, isoplanatic angle θAO and wavefront coherence time τAO) related to the C n2 profiles above the Tibetan Plateau are investigated for astronomical applications by using the Weather Research and Forecasting (WRF) model. Radiosonde measurements from a field campaign at Lhasa station above the Tibetan Plateau are used to quantify the ability of this model. The results show that the C n2 profile decreases rapidly in the surface layer, increasing with height from the boundary layer to low stratosphere, and decreases gradually in the high free atmosphere. From the whole campaign measurements above the Tibetan Plateau, the mean r0 is 8.64 cm, the mean ɛ is 1.55'', the mean θAO is 0.42'' and the mean τAO is 1.89 ms, and the comparison with the other world's leading observatory sites have been presented. In addition, such as the bias and the root-mean-squared error are used to quantify the performance of the WRF model. In spite of the model performance in reconstructing the meteorological parameters is reasonable in general, the uncertainty in quantifying the C n2 profiles and the integrated parameters are not negligible in some cases. The main results of this study tell us that the WRF model could provide a useful resource to design, monitor the performance of, and even optimize the operation of sophisticated Adaptive Optics (AO) systems.

15.
J Opt Soc Am A Opt Image Sci Vis ; 37(11): 1785-1794, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-33175755

RESUMEN

The distribution of optical turbulence (Cn2 profiles) is the fundamental parameter closely related to the design and application of optoelectronic systems. Since systematic direct measurements of optical turbulence for many climates and seasons are not available, it is useful to estimate Cn2 effectively from the routine meteorological parameters. The Cn2 profiles are estimated by routine meteorological parameters based on the Tatarskii model, and the estimated results are compared with the corresponding radiosonde measurements from the field campaigns at Rongcheng (122.37∘E, 37.15∘N), Taizhou (121.42∘E, 28.62∘N), and Dachaidan (95.35∘E, 37.74∘N) in China. The agreement between the estimation model and the measurement is very close, except for a portion of the atmosphere where it showed considerable difference. Additionally, statistical operators are used to quantify the performance of the estimated model, and the statistical results also show that the estimated and measured Cn2 profiles are consistent well. Furthermore, the integrated parameters (such as the Fried parameter, r0) from radiosonde measurement are 7.92 cm, 5.39 cm, and 3.68 cm at Rongcheng, Taizhou, and Dachaidan, respectively. Therefore, the Cn2 profiles and their characteristics in these typical climate sites provide useful information to assess the effect of laser transmission in the atmosphere, which are usually used in the design of optoelectronic systems and astronomical site testing.

16.
Heart Vessels ; 35(6): 825-834, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31786644

RESUMEN

The femoral approach with the Needle's Eye Snare (NES) is often used for bailout after failure of the superior approach for transvenous lead extraction (TLE). The safety and efficacy of the NES as a first-line tool for TLE remain unclear. The medical records of patients who underwent TLE via the femoral approach utilizing the NES from May 2014 to June 2019 in Peking University People's Hospital were retrospectively reviewed. Nine hundred and eighty-five leads were extracted in 492 patients (369 men; mean age 72.8 ± 29.0 years). The median (range) number of leads extracted per patient was 2 (1-6). The mean indwelling time of all extracted leads was 112.6 ± 52.0 months. The complete procedure success rate, clinical success rate, and failure rate were 94.1% (463/492), 97.8% (481/492), and 1.1% (11/492), respectively. Major complications including death occurred in nine patients (1.9%), of whom eight developed cardiac tamponade. Among these eight patients, emergency pericardiocentesis followed by rescue surgical repair if necessary was successful in 6 (75.0%) and failed in 2 (25.0%). No significant differences were found in the clinical success rate or major complications rate between patients with pacemakers and implantable cardioverter defibrillators, or between patients with infected and uninfected leads. A femoral approach with the NES is safe and effective for TLE of both pacing and defibrillator leads and could be considered a first-line approach. Cardiac tamponade was the most frequent cardiovascular complication. A strategy of emergency pericardiocentesis followed by a rescue surgical approach seems to be reasonable technique to treat a cardiac tamponade.


Asunto(s)
Cateterismo Periférico , Desfibriladores Implantables , Remoción de Dispositivos , Arteria Femoral , Marcapaso Artificial , Adulto , Anciano , Anciano de 80 o más Años , Beijing , Cateterismo Periférico/efectos adversos , Cateterismo Periférico/mortalidad , Remoción de Dispositivos/efectos adversos , Remoción de Dispositivos/mortalidad , Femenino , Arteria Femoral/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Punciones , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento , Adulto Joven
17.
Biochem Biophys Res Commun ; 517(1): 8-14, 2019 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-31307785

RESUMEN

BACKGROUND: Atrial fibrillation (AF) is the most common progressive cardiac arrhythmia and is often associated with rapid contraction in both atria and ventricles. The role of atrial energy and metabolic homeostasis in AF progression is under-investigated. OBJECTIVES: To determine the remodeling of energy metabolism during persistent AF and the effect of eplerenone (EPL), an aldosterone inhibitor, on metabolic homeostasis. METHODS: A nonsustained atrial pacing sheep model was developed to simulate the progression of AF from paroxysmal to persistent. Metabolomic and proteomic analyses at termination of the experiment were used to analyze atrial tissues obtained from sheep in sham, sugar pill (SP) and EPL-treated groups. RESULTS: Proteomic analysis indicated that compared to the sham group, in SP group, fatty acid (FA) synthesis, FA oxidation, tricarboxylic acid (TCA) cycle processes and amino acids (AAs) transport and metabolism were reduced, while glycolytic processes were increased. In metabolomic analysis, the levels of intermediate metabolites of the glycolytic pathways, including 2-phosphoglyceric acid (2 PG), 1,3-bisphosphoglyceric acid (1,3 PG), and pyruvate, HBP (uridine diphosphate-N-acetylglucosamine, UDP-GlcNAc), TCA (citrate) and AAs were greater while the levels of the majority of lipid classes, including phosphatidic acid (PA), phosphatidylcholine (PC), phosphatidylglycerol (PG), glycerophosphoglycerophosphates (PGP), glycerophosphoinositols (PI) and glycerophosphoserines (PS), were decreased in the atria of SP group than in those of sham group. EPL-pretreatment decreased the expression of glut4 and increased the content of acylcarnitines and lipids, such as lyso phospholipids, phospholipids and neutral lipids. CONCLUSION: In the metabolic remodeling during AF, glucose and lipid metabolism were up- and down-regulated, respectively, to sustain TCA cycle anaplerosis. EPL partialy reversed the metabolic shifting.


Asunto(s)
Fibrilación Atrial/metabolismo , Metabolismo Energético , Miocardio/metabolismo , Animales , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/patología , Ciclo del Ácido Cítrico/efectos de los fármacos , Modelos Animales de Enfermedad , Metabolismo Energético/efectos de los fármacos , Eplerenona/uso terapéutico , Glucosa/metabolismo , Homeostasis/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Redes y Vías Metabólicas/efectos de los fármacos , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico , Miocardio/patología , Ovinos
18.
Biol Pharm Bull ; 42(3): 462-467, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30587668

RESUMEN

Panax notoginseng saponins (PNS) have been widely used in China to treat stroke. Accumulating evidence has found that microRNA (miR)-155 plays critical roles in the pathology of ischemic stroke. Here we investigated whether PNS plays a protective effect against oxygen-glucose deprivation/reoxygenation (OGD/R)-induced focal inflammation and injury in SH-SY5Y cells by regulating miR-155 expression. Treatment with PNS at a concentration less than 160 µg/mL had no effect on the proliferation of SH-SY5Y cell. In OGD/R-induced SH-SY5Y cells, 160 µg/mL PNS treatment promoted cell proliferation and cell cycle progression, as well as decreased inhibited apoptosis and miR-155 expression. However, overexpression of miR-155 attenuated the promotion effects of PNS on cell proliferation and cell cycle, apoptosis inhibition in OGD/R-induced SH-SY5Y cells. Moreover, 160 µg/mL PNS treatment decreased the levels of interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-α (TNF-α) in OGD/R-induced SH-SY5Y cells, whereas overexpression of miR-155 reversed PNS-induced decreases in the levels of IL-1ß, IL-6, and TNF-α in OGD/R-treated SH-SY5Y cells. In conclusion, PNS attenuated OGD/R-induced injury in human undifferentiated SH-SY5Y cells by regulating the expression of inflammatory factors through miR-155.


Asunto(s)
Glucosa/metabolismo , Inflamación/metabolismo , MicroARNs/metabolismo , Oxígeno/metabolismo , Panax notoginseng/química , Saponinas/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Citocinas/genética , Citocinas/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Glucosa/farmacología , Humanos , Inflamación/genética , MicroARNs/genética , Oxígeno/farmacología , Saponinas/química
19.
Cell Physiol Biochem ; 45(1): 281-290, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29402868

RESUMEN

BACKGROUND/AIMS: To investigate the changes in peripheral blood Treg/Th17 cell balance and its significance in patients with chronic renal failure (CRF) and cognitive impairment. METHODS: A total of 71 patients with CRF were enrolled as a study group. The patients were divided into a cognitive impairment group and a normal cognitive function group according to the Mini-Mental State Examination (MMSE). Peripheral blood Treg and Th17 cells were analyzed by flow cytometry and their relevant cytokines (IL-17, IL-10 and TGF-ß) and other biochemical indicators, including C-reactive protein (CRP) and IL-6, were determined by ELISA. RESULTS: Thepatients with both CRF and cognitive impairment were older than the cognitive normal groups. Peripheral blood Treg cells by Flow cytometry (the CRF cognitive impairment group 5.57±1.3%, CRF group with normal cognitive function 7.5 ± 0.9% and normal control group 9.7 ± 1.7%,P<0.05) and its related cytokines (IL-10 and TGF-ß) by ELISA detection were lower in the group with cognitive impairment than in the group without cognitive impairment ( IL-10, 7.4±4.2 pg/mL, 13.8±3.9 pg/mL, 18.3±3.2 pg/mL; TGF-ß 335.6±175.3 pg/mL, 512.7 ± 114.6 pg/mL, 953.8±373.4 pg/mL P < 0.05, respectively).However, Th17 cell numbers (the CRF cognitive impairment group 3.3 ± 0.7%, CRF group with normal cognitive function2.2 ± 0.5% and normal control group 1.5 ± 0.3%),and cytokine levels (IL-17, IL-6 and CRP) were higher in the group with cognitive impairment IL-6 (21.3 ± 5.1 pg/mL), IL-17 (18.5 ± 4.2 pg/mL) and CRP (20.3 ± 5.9 mg/L) in the CRF group with cognitive impairment when compared with the CRF group and normal cognitive function (12.2 ± 4.5 pg/mL, 12.1 ± 3.7 pg/mL and 13.5 ± 4.6 mg/L, respectively) or the normal control group (9.2 ± 5.8 pg/mL, 7.4 ± 2.6 pg/mL and 3.2 ± 1.3 mg/L, respectively, P<0.05). The frequencies of Treg in patients with CRF were positively correlated with the MMSE scores ((r = 0.518, P < 0.05), but the Th17 numbers were negatively correlated (r = -0.435, P < 0.05). CONCLUSION: An imbalance of peripheral blood Treg/Th17 cells is associated with cognitive impairment in patients with CRF.


Asunto(s)
Disfunción Cognitiva/diagnóstico , Fallo Renal Crónico/diagnóstico , Linfocitos T Reguladores/metabolismo , Células Th17/metabolismo , Anciano , Anciano de 80 o más Años , Proteína C-Reactiva/análisis , Antígenos CD4/metabolismo , Estudios de Casos y Controles , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/inmunología , Femenino , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Humanos , Interleucina-10/sangre , Interleucina-17/sangre , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Interleucina-6/sangre , Fallo Renal Crónico/complicaciones , Leucocitos Mononucleares/citología , Masculino , Persona de Mediana Edad , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/inmunología , Células Th17/citología , Células Th17/inmunología
20.
Opt Express ; 24(12): 13303-15, 2016 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-27410347

RESUMEN

The methods to obtain atmospheric refractive index structure constant (Cn2) by instrument measurement are limited spatially and temporally and they are more difficult and expensive over the ocean. It is useful to forecast Cn2 effectively from Weather Research and Forecasting Model (WRF) outputs. This paper introduces a method that WRF Model is used to forecast the routine meteorological parameters firstly, and then Cn2 is calculated based on these parameters by the Bulk model from the Monin-Obukhov similarity theory (MOST) over the ocean near-surface. The corresponding Cn2 values measured by the micro-thermometer which is placed on the ship are compared with the ones forecasted by WRF model to determine how this method performs. The result shows that the forecasted Cn2 is consistent with the measured Cn2 in trend and the order of magnitude as a whole, as well as the correlation coefficient is up to 77.57%. This method can forecast some essential aspects of Cn2 and almost always captures the correct magnitude of Cn2, which experiences fluctuations of two orders of magnitude. Thus, it seems to be a feasible and meaningful method that using WRF model to forecast near-surface Cn2 value over the ocean.

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