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1.
Anal Methods ; 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33629983

RESUMO

Metal-organic frameworks (MOFs) are highly ordered framework systems composed of metal centers and organic linkers formed through coordination bonds. The diversity of metal elements and easily modified organic ligands, together with controllable synthetic approaches, gives rise to the designability of various MOF structures and topologies and the capability of MOFs to be functionalized. Their structural diversity provides MOFs with many unique properties, such as permanent porosity, flexible structures, thermostability, and high adsorption capacity, leading to great practicability in technical applications. In this review, we concentrate on the applications of MOFs in the field of gas chromatography, high-performance liquid chromatography, and the enrichment of biomolecules, based on rational arrangements in the structures and functions of MOFs. Moreover, we emphasize the importance of structural and chemical regulations for the improvement of separation efficiency.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33619619

RESUMO

Rapid environmental microorganism (EM) classification under microscopic images would help considerably identify water quality. Because of the development of artificial intelligence, a deep convolutional neural network (CNN) has become a major solution for image classification. Three popular CNNs, referred to as ResNet50, Vgg16, and Inception-v3, were transferred to identify the EM images present on the Environmental Microorganism Dataset (EMDS), and EMAD was the small dataset, which only has 294 EM images with 21 EM classes. Besides data augmentation, optimizing the fully connected layer of CNN, i.e., both optimally fine-tuned neuron number and dropout rate, was adopted to enhance the performance produced by CNN. The discussions on the causes of the accuracy improved by optimization are also provided. The results showed that the Inception-v3 model obtained 84.9% of the accuracy and performed better than the other two famous CNNs. Also, the implement of data augmentation enhanced the performance of Inception-v3 on EMDS. To add to that, the optimized Inception-v3 model archived 90.5% of the accuracy, and this result demonstrated the improvement effect obtained by using genetic algorithm (GA) to optimize the fully connected layer of the Inception-v3. Therefore, the optimize Inception-v3 with data augmentation process obtained the accuracy of 92.9% and improved almost 21% higher than that obtained from the famous Vgg16. In addition, the optimized Inception-v3 would need less neurons, when compared with that of the optimized Vgg16 possibly. This optimized Inception-v3 could provide a solution to the EM classification in microscope with a digital camera system.

3.
Ann Palliat Med ; 10(1): 333-339, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33545768

RESUMO

BACKGROUND: Tuberculosis (TB) is a global public health problem and China is one of the 22 countries with a high TB burden. The characteristics of the epidemic of TB in China include a high rate of infection, high prevalence, serious drug resistance, and low rate of decline and the TB epidemic in Guizhou Province is more serious than in other parts of the country. We conducted a survey during September and October 2019 to investigate public awareness of core TB information. METHODS: A multi-stage, stratified random sampling method was used to survey individuals at 18 investigation sites on their awareness of core information related to TB. SPSS22.0 software was used to analyze data and P<0.05 was considered statistically different. RESULTS: Of the 10,563 questionnaires collected, the total awareness rate of TB, the awareness rates of transmission, symptoms, treatment (doctor visit way), preferential policies, and prognosis of TB were 62.5% (95% CI: 0.6169-0.6329), 62.8% (95% CI: 0.6190-0.6374), 75.2% (95% CI: 0.7434-0.7599), 66.4% (95% CI: 0.6553-0.6733), 39.1% (95% CI: 0.3819-0.4005), 61.2% (95% CI: 0.6029-0.6215) respectively. The personal awareness qualified rate was 45.0% (95% CI: 0.4404-0.4594) and multivariate logistic regression analysis showed that education was the main factor associated with awareness of TB. CONCLUSIONS: Public awareness of the core information about TB is low in Guizhou Province. Intensive education about TB should be carried out.

4.
Biomed Res Int ; 2021: 8875023, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33575352

RESUMO

Background: Monolithic restorations made of translucent yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) have become popular over the past few decades. However, whether aging affects the color and translucency of monolithic translucent Y-TZP is unclear. Objective: The aim of this systematic review and meta-analysis of in vitro studies was to evaluate the effects of aging on the color and translucency of monolithic translucent Y-TZP ceramics. Materials and Methods: This systematic review/meta-analysis was reported according to the PRISMA statement and registered in the OSF registries (https://osf.io/5qjmu). Four databases including Medline via the PubMed, Embase, and Web of Science databases and the Cochrane Library were searched using no publication year and language limits. The last search was executed on November 20, 2020. In vitro studies comparing the translucency and/or color of monolithic translucent Y-TZP ceramics before and after simulated aging were selected. Meta-analyses were performed using Review Manager software (version 5.3, Cochrane Collaboration, Oxford, UK) with random-effects models at a significance level of 0.05. A risk-of-bias assessment was also performed for the included studies. Results: Of the 188 potentially relevant studies, 13 were included in the systematic review. The hydrothermal aging duration ranged from 1 to 100 h at relatively similar temperatures (~134°C). In the general meta-analyses, the aged Y-TZP ceramics exhibited similar translucency parameter (TP), L∗, and b∗ values compared with the nonaged controls (P = .73, P = .49, and P = .62, respectively). Moreover, there was a significant difference between the aged and nonaged Y-TZP ceramics in the a∗ value (P = .03; MD = -0.26; 95% CI = -0.51 to - 0.02), favoring the nonaged Y-TZP ceramics. The subgroup analyses showed that the duration of aging contributed to changes in the translucency and color of the Y-TZP ceramics. Conclusions: The optical properties of monolithic translucent Y-TZP ceramics were stable after hydrothermal aging at 134°C and 0.2 MPa for ≤20 h. Moreover, clinically unacceptable changes in the translucency and color of monolithic translucent Y-TZP ceramics were found after hydrothermal aging for >20 h.

5.
BMC Genomics ; 22(1): 135, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632122

RESUMO

BACKGROUND: The ladybird beetle Cryptolaemus montrouzieri Mulsant, 1853 (Coleoptera, Coccinellidae) is used worldwide as a biological control agent. It is a predator of various mealybug pests, but it also feeds on alternative prey and can be reared on artificial diets. Relatively little is known about the underlying genetic adaptations of its feeding habits. RESULTS: We report the first high-quality genome sequence for C. montrouzieri. We found that the gene families encoding chemosensors and digestive and detoxifying enzymes among others were significantly expanded or contracted in C. montrouzieri in comparison to published genomes of other beetles. Comparisons of diet-specific larval development, survival and transcriptome profiling demonstrated that differentially expressed genes on unnatural diets as compared to natural prey were enriched in pathways of nutrient metabolism, indicating that the lower performance on the tested diets was caused by nutritional deficiencies. Remarkably, the C. montrouzieri genome also showed a significant expansion in an immune effector gene family. Some of the immune effector genes were dramatically downregulated when larvae were fed unnatural diets. CONCLUSION: We suggest that the evolution of genes related to chemosensing, digestion, and detoxification but also immunity might be associated with diet adaptation of an insect predator. These findings help explain why this predatory ladybird has become a successful biological control agent and will enable the optimization of its mass rearing and use in biological control programs.

6.
Cell ; 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33545088

RESUMO

Rich fossil evidence suggests that many traits and functions related to terrestrial evolution were present long before the ancestor of lobe- and ray-finned fishes. Here, we present genome sequences of the bichir, paddlefish, bowfin, and alligator gar, covering all major early divergent lineages of ray-finned fishes. Our analyses show that these species exhibit many mosaic genomic features of lobe- and ray-finned fishes. In particular, many regulatory elements for limb development are present in these fishes, supporting the hypothesis that the relevant ancestral regulation networks emerged before the origin of tetrapods. Transcriptome analyses confirm the homology between the lung and swim bladder and reveal the presence of functional lung-related genes in early ray-finned fishes. Furthermore, we functionally validate the essential role of a jawed vertebrate highly conserved element for cardiovascular development. Our results imply the ancestors of jawed vertebrates already had the potential gene networks for cardio-respiratory systems supporting air breathing.

7.
Oral Oncol ; 115: 105190, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33581503

RESUMO

OBJECTIVES: The importance of treating the bilateral neck in lateralized small oral cavity squamous cell carcinoma (OCC) is unclear. We sought to define the incidence and predictors of contralateral neck failure (CLF) in patients who underwent unilateral treatment. MATERIALS AND METHODS: We performed a multi-institutional retrospective study of patients with pathologic T1-T2 (AJCC 7th edition) OCC with clinically node negative contralateral neck who underwent unilateral treatment with primary surgical resection ± adjuvant radiotherapy between 2005 and 2015. Incidence of CLF was estimated using the cumulative incidence method. Clinicopathological factors were analyzed by univariate (UVA) and multivariate analysis (MVA) for possible association with CLF. Kaplan-Meier analysis was used to estimate overall survival (OS). RESULTS: 176 patients were evaluated with a median of 65.9 months of follow-up. Predominant pathologic T-stage was T1 (68%), 8.5% of patients were N1, 2.8% were N2b. Adjuvant radiotherapy was delivered to 17% of patients. 5-year incidence of CLF was 4.3% (95% CI 1.2-7.4%). Depth of invasion (DOI) > 10 mm and positive ipsilateral neck node were significant predictors for CLF on UVA. DOI > 10 mm remained significant on MVA (HR = 6.7, 95% CI 1.4-32.3, p = 0.02). The 2- and 5-year OS was 90.6% (95% CI 86.2-95.0%) and 80.6% (95% CI 74.5-86.8%), respectively. CONCLUSION: Observation of the clinically node negative contralateral neck in small lateralized OCC can be a suitable management approach in well selected patients, however caution should be applied when DOI upstages small but deeply invasive tumors to T3 on 8th edition AJCC staging.

8.
Exp Gerontol ; 147: 111272, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33549820

RESUMO

PURPOSE: Osteosarcopenic adiposity (OSA), which is described as the concurrent occurrence of osteopenia, sarcopenia, and adiposity, can lead to frailty and increase the risk of physical disability in elderly women. Progressive elastic band resistance exercise training (peRET) is considered a safe and feasible exercise intervention for elderly women with sarcopenic obesity. This study investigated the effects of elastic band resistance exercise on the physical capacity and body composition of elderly women with osteosarcopenic adiposity. METHOD: A total of 15 and 12 women were randomly assigned to the experimental (12 weeks of resistance exercise) and control groups (no exercise intervention), respectively. Lean mass (measured using a dual-energy X-ray absorptiometer) and physical capacity assessments (such as timed up and go test and single leg stance tests) were conducted at baseline, 12 weeks (end of intervention), and 6 months after the intervention. Outcome differences within the study and control groups were analyzed using repeated-measures analysis of variance with a post-hoc test. The Mann-Whitney U test was used to examine differences between groups at different time points. RESULTS: After the intervention, no body composition changes in muscle mass and fat were observed between the study and control groups. Moreover, muscle mass and fat body composition did not significantly differ at different time points. The bone density was higher in the study group, with a higher T-score than their baseline values, but did not significantly differ compared with the control group. The study group exhibited more improved physical function than the control group, but the effect did not last after 6 months of follow-up. CONCLUSIONS: A 12-week progressive elastic band resistance training program effectively increased the physical capacity and improved the bone density; however, without persistent training, the positive effect diminished at 6-month follow-up.

10.
Aging (Albany NY) ; 13(3): 3176-3189, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33561834

RESUMO

To establish an effective nomogram for predicting in-hospital mortality of COVID-19, a retrospective cohort study was conducted in two hospitals in Wuhan, China, with a total of 4,086 hospitalized COVID-19 cases. All patients have reached therapeutic endpoint (death or discharge). First, a total of 3,022 COVID-19 cases in Wuhan Huoshenshan hospital were divided chronologically into two sets, one (1,780 cases, including 47 died) for nomogram modeling and the other (1,242 cases, including 22 died) for internal validation. We then enrolled 1,064 COVID-19 cases (29 died) in Wuhan Taikang-Tongji hospital for external validation. Independent factors included age (HR for per year increment: 1.05), severity at admission (HR for per rank increment: 2.91), dyspnea (HR: 2.18), cardiovascular disease (HR: 3.25), and levels of lactate dehydrogenase (HR: 4.53), total bilirubin (HR: 2.56), blood glucose (HR: 2.56), and urea (HR: 2.14), which were finally selected into the nomogram. The C-index for the internal resampling (0.97, 95% CI: 0.95-0.98), the internal validation (0.96, 95% CI: 0.94-0.98), and the external validation (0.92, 95% CI: 0.86-0.98) demonstrated the fair discrimination ability. The calibration plots showed optimal agreement between nomogram prediction and actual observation. We established and validated a novel prognostic nomogram that could predict in-hospital mortality of COVID-19 patients.

11.
Fertil Steril ; 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33622565

RESUMO

OBJECTIVE: To depict the PIWI-interacting RNA (piRNA) profile in oocytes from patients with recurrent oocyte maturation arrest (ROMA) and explore the piRNA candidates associated with the disease. DESIGN: An observational study. SETTING: Academic research unit. PATIENT(S): Sixteen ROMA patients who provided 140 immature oocytes that arrested at metaphase I, and 146 control patients who provided 420 oocytes for in vitro culture that were collected at the stages of germinal vesicle (GV), metaphase I (MI), and MII. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Expression profiles of piRNA and quantitative reverse-transcription polymerase chain reaction (qRT-PCR) validating data of piR-hsa-17139 and its target genes. RESULT(S): After the piRNA profile was established using piRNA sequencing and hierarchical clustering, the target genes of the piRNA were predicted by bioinformatics databases and matched with mRNA sequencing data. The piRNA expression profiles showed a greater quantity of differentially expressed piRNAs in the older-stage oocytes compared with the early-stage oocytes. The piRNA and mRNA sequencing data indicated that the most affected genes were mainly concentrated in the extracellular matrix (ECM) pathway. Based on the comparison of the piRNA and mRNA sequencing data, four differentially expressed piRNAs were associated with modulation of those ECM pathway genes. The qRT-PCR validation confirmed that piR-hsa-17139 was the only up-regulated piRNA, and its target ECM genes were suppressed in ROMA oocytes. The expression level of piR-hsa-17139 declined slightly while the expression of its target ECM genes plunged dramatically during the development of normal oocytes. CONCLUSION(S): As the important genome monitors in gametogenesis, abnormally expressed piRNAs may affect the expression of ECM modulating genes, which subsequently contributes to ROMA.

12.
Chem Commun (Camb) ; 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33592078

RESUMO

We report the design, chemical synthesis, and flexizyme-catalyzed transfer RNA (tRNA) acylation of a variety of fluorescent amino acids (FAAs). The fluorescent groups include pyrene, coumarin, nitrobenzoxadiazole, and fluorescein variants. We further demonstrate site-specific incorporation of the FAAs into peptides by the ribosome in vitro through genetic code reprogramming.

13.
J Org Chem ; 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33567820

RESUMO

Sulfuryl fluoride is a valuable reagent for the one-pot activation and derivatization of aliphatic alcohols, but the highly reactive alkyl fluorosulfate intermediates limit both the types of reactions that can be accessed as well as the scope. Herein, we report the SO2F2-mediated alcohol substitution and deoxygenation method that relies on the conversion of fluorosulfates to alkyl halide intermediates. This strategy allows the expansion of SO2F2-mediated one-pot processes to include radical reactions, where the alkyl halides can also be exploited in the one-pot deoxygenation of primary alcohols under mild conditions (52-95% yield). This strategy can also enhance the scope of substitutions to nucleophiles that are previously incompatible with one-pot SO2F2-mediated alcohol activation and enables substitution of primary and secondary alcohols in 54-95% yield. Chiral secondary alcohols undergo a highly stereospecific (90-98% ee) double nucleophilic displacement with an overall retention of configuration.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33606065

RESUMO

The expression status of programmed cell death-ligand 1/programmed cell death 1 (PD-L1/PD-1) and the infiltration of CD8+ T cells in tumor tissues are considered to be related to immunotherapy efficacy and patient prognosis. The purpose of this study is to clarify the prognostic value of the PD-L1/PD-1/CD8 axis, and to develop and validate a comprehensive scoring system based on multiple immune variables to predict cancer survival of upper tract urothelial carcinoma (UTUC) after radical nephroureterectomy (RNU). The immunohistochemical method was used to detect the expression of PD-L1, PD-1, and CD8 in cancer tissues of UTUC patients after RNU. Then, an immunoscore was constructed using the least absolute shrinkage and selection operator (LASSO) Cox regression model in the training cohort (n = 120), and it was verified in the validation cohort (n = 54). We found that infiltration of PD-L1+ immune cells (ICs), stromal PD-1+ tumor-infiltrating lymphocytes (TILs), and intratumoral CD8+ TILs was associated with poor overall survival (OS). The immunoscore based on the three immune variables further divided the patients into low- and high-risk groups, and there was a significant difference in the survival rate. A nomogram was constructed by combining tumor-node-metastasis (TNM) stage and immunoscore, and the area under the curve of the receiver-operating characteristic (ROC) (0.78) for predicting 5-year mortality was better than that of the TNM stage (0.70) and immunoscore (0.76). Our results show that the PD-L1/PD-1/CD8 axis-based classifier have potential clinical application to predict cancer survival of UTUC patients after RNU.

15.
Cells ; 10(2)2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33572536

RESUMO

Although several modes of reprogramming have been reported in different cell types during iPSC induction, the molecular mechanism regarding the selection of different modes of action is still mostly unknown. The present study examined the molecular events that participate in the selection of such processes at the onset of somatic reprogramming. The activity of STAT3 versus that of Erk1/2 reversibly determines the reprogramming mode entered; a lower activity ratio favors the deterministic process and vice versa. Additionally, extraneous E-cadherin facilitates the early events of somatic reprogramming, potentially by stabilizing the LIF/gp130 and EGFR/ErbB2 complexes to promote entry into the deterministic process. Our current findings demonstrated that manipulating the pSTAT3/pErk1/2 activity ratio in the surrounding milieu can drive different modes of action toward either the deterministic or the stochastic process in the context of OSKM-mediated somatic reprogramming.

16.
Plant Physiol ; 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33576799

RESUMO

Trichomes are specialized epidermal cells that act as barriers against biotic and abiotic stresses. Although the formation of trichomes on hairy organs is well studied, the molecular mechanisms of trichome inhibition on smooth organs is still largely unknown. Here, we demonstrate that the CINCINNATA (CIN)-like TEOSINTE BRANCHED1/CYCLOIDEA/PCF (TCP) transcription factors inhibit the formation of trichomes on cotyledons in Arabidopsis (Arabidopsis thaliana). The tcp2/3/4/5/10/13/17 septuple mutant produces cotyledons with ectopic trichomes on the adaxial sides. The expression patterns of TCP genes are developmentally regulated during cotyledon development. TCP proteins directly interact with GLABRA3 (GL3), a key component of the MYB transcription factor/basic helix-loop-helix domain protein/WD40-repeat proteins (MYB-bHLH-WD40, MBW) complex essential for trichome formation, to interfere with the transactivation activity of the MBW complex in cotyledons. TCPs also disrupt the MBW complex-R3 MYB negative feedback loop by directly promoting the expression of R3 MYB genes, which enhances the repression of the MBW complex. Our findings reveal a molecular framework in which TCPs suppress trichome formation on adaxial sides of cotyledons by repressing the activity of the MBW complex at the protein level and the transcripts of R3 MYB genes at the transcriptional level.

17.
Toxins (Basel) ; 13(2)2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33562867

RESUMO

Zearalenone (ZEA) is a mycotoxin of the Fusarium genus that can cause endoplasmic reticulum (ER) stress and Apoptosis in bovine mammary epithelial cells (MAC-T). Polydatin (PD), a glycoside purified from Polygonum cuspidatum, has antioxidant properties. This study aimed to explore whether PD can alleviate ZEA-induced damage on bovine mammary epithelial cells (MAC-T). We found that incasing the concentration of ZEA (0, 7.5, 15, 30, 60, 90, 120, and 240 µM) gradually decreased the cell viability. PD treatment alone at 5, 10, and 20 µM did not affect cell viability. Follow-up studies then applied 30 µM of ZEA and 5 µM of PD to treat cells; the results showed that the ZEA + PD treatment group effectively reduced cell oxidative damage compared with the ZEA treatment group. The qPCR analysis showed that ZEA treatment significantly up-regulated the expression of ER stress-related genes, relative to the control. However, adding PD significantly down-regulated the expression of ER stress-related genes. The cell apoptosis detection results showed that, compared with the ZEA treatment group, the ZEA + PD treatment group down-regulated the Bax gene and up-regulated the Bcl-2 gene expressions, which reduced the cell apoptosis rate and Caspase-3 activity. Taken together, these results indicate that PD reduces ZEA-induced apoptosis by inhibiting oxidative damage and ER stress.

18.
Eur Radiol ; 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33564956

RESUMO

OBJECTIVE: To evaluate the feasibility of CT angiography (CTA) for assessing anterior choroidal artery (AChA) and posterior communicating artery (PComA) dilatation in patients with moyamoya syndrome (MMS). METHODS: Eighty-eight MMS patients who underwent digital subtraction angiography (DSA) and CTA within 1 month were enrolled. The AChA was graded using both DSA and CTA. Given the features of dual blood supply, DSA was firstly used for grading of the PComA. Then, the calibers of PComA, P1 or P2 segment of the posterior cerebral artery (PCA), were recorded from CTA. Taking DSA as a reference standard, the optimal cutoff values of the PComA/P1 or PComA/P2 were calculated to determine the dilatation of PComA. Both the AChA and PComA were classified as extreme dilatation (ED, grade 2) or non-extreme dilatation (NED, grade 0 or 1). RESULTS: The AChA was evaluated in 149 affected hemispheres of 88 patients while the PComA was evaluated in 70 affected hemispheres of 49 patients. The sensitivity and specificity of CTA in diagnosing AChA-ED were 92% and 93.5% respectively. Both the PComA/P1 (p < 0.001) and PComA/P2 (p = 0.4) ratios were increased in the PComA-ED group with the former yielding a better detecting performance than the latter (AUC = 0.92 vs 0.85, p = 0.046). When using 0.71 as a cutoff value, the sensitivity and specificity of the PComA/P1 ratio for diagnosis of PComA-ED cases were 91.3% and 83.3% respectively. CONCLUSIONS: CTA could be used for the AChA classification in MMS patients, while a PComA/P1 ratio greater than 0.71 indicates the existence of PComA-ED. KEY POINTS: • CTA showed a high sensitivity, specificity, and accuracy in diagnosing AChA-ED in patients with MMS. • PComA/P1 ratio greater than 0.71 on CTA signified an extremely dilated PComA. • CTA could be used to assess the dilatation of AChA and PComA in MMS patients, especially for routine postoperative follow-up.

19.
Sci Total Environ ; 773: 144818, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33592482

RESUMO

To investigate the spatial and vertical distribution of atmospheric pollutants (SO2, NOx, CO and O3), aircraft-based measurements (model: Yun-12, 12 flights, 27 h total flight time) were conducted from near the surface up to 2400 m over the Beijing-Tianjin-Hebei (BTH) region between June 17th and July 22nd 2016. The results showed that high concentrations of primary gaseous pollutants (SO2, NOx, CO) were generally present in Beijing, Tianjin, Langfang and Tangshan areas, while high values of O3 frequently appeared in areas far from the city. The flights at noon and dusk measured higher O3 concentrations at 600 m and lower O3 concentrations at higher altitudes, implying a strong influence by photochemical production. Back trajectory analysis suggested that the high levels of gaseous pollutants, especially at 600 m, were associated with pollution sources transported from the southerly direction during the observation period. The first simultaneous vertical distribution measurements using aircraft and tethered balloon were conducted in Gaocun (a rural site between Beijing and Tianjin) on June 17th. The results indicated that an inversion layer at the top of the planetary boundary layer (PBL) significantly suppressed vertical exchange through the PBL and resulted in a "two-layer" vertical distribution of pollutants above and below the PBL. Additionally, a residual high O3 layer (79.9 ± 2.5 ppb, 500-1000 m) was observed above the PBL, and it contributed to the surface peak O3 level at noon through downward transport along with the opening up of the PBL. These results indicate that coupled effects of horizontal and vertical transport should be investigated in future studies to improve the chemical transport models used to study the vertical distribution and regional transport over the BTH region.

20.
BMC Geriatr ; 21(1): 125, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33593292

RESUMO

BACKGROUND: Frailty increases the adverse outcomes of clinical heart failure; however, the relationship between frailty and stage-B heart failure (SBHF) remains unknown. We aimed to explore the epidemiology and predictive value of frailty in older adults with SBHF. METHODS: A prospective cohort of SBHF inpatients aged 65 years or older who were hospitalized between September 2018 and February 2019 and were followed up for 6 months were included. SBHF was defined as systolic abnormality, structural abnormality (left ventricular enlargement, left ventricular hypertrophy, wall motion abnormalities, valvular heart disease), or prior myocardial infarction. Frailty was assessed by the Fried frailty phenotype. Multivariable Cox proportional hazards regression was used to explore the independent risk and prognostic factors. RESULTS: Data of 443 participants (age: 76.1 ± 6.79 years, LVEF: 62.8 ± 4.92%, men: 225 [50.8%], frailty: 109 [24.6%]) were analyzed. During the 6-month follow-up, 83 (18.7%) older SBHF inpatients experienced all-cause mortality or readmission, and 29 (6.5%) of them developed clinical HF. Frail individuals had a 1.78-fold (95%CI: 1.02-3.10, P = 0.041) higher risk of 6-month mortality or readmission and a 2.83-fold (95%CI 1.24-6.47, P = 0.014) higher risk of developing clinical HF, independent of age, sex, left ventricular ejection fraction, and N-terminal pro-B-type natriuretic peptide level. CONCLUSIONS: Frailty is common in older SBHF inpatients and should be considered to help identify individuals with an increased risk of mortality or readmission, and developing clinical HF. TRIAL REGISTRATION: ChiCTR1800017204 .

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