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1.
J Med Virol ; 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33565614

RESUMO

To understand host-pathogen interactions and develop effective prevention and control strategies for human adenovirus (HAdV), it is essential to explore the characteristics of HAdV shedding. Hospitalized children <14 years who had severe HAdV pneumonia were tested for HAdV DNA by quantitative real-time PCR in nasopharyngeal aspirate (NPA). A total of 132 children were enrolled, including 102 patients with HAdV type 7 (HAdV-7) infection and 12 patients with HAdV type 3 (HAdV-3) infection. A total of 1372 qualified NPA samples were collected. There was a significant negative correlation between the viral load of HAdV and the course of the disease (Spearman r = -0.547, p = .000). HAdV-7 load decreased at a rate of 0.089 log10 copies/mL per day (95% CI: -0.096 to -0.081; R2 = 0.332), and the duration of viral shedding was predicted to be 96.9 days (y = 8.624-0.089x). However, HAdV-3 load decreased more quickly (95% CI: - 0.229 to - 0.143; R2 = 0.403), and the duration of viral shedding was 51.4 days (y = 9.558-0.186x). The median viral load of the HAdV-7 group at weeks 2 and 3, and more than 3 weeks postinfection was higher than that of the HAdV-3 group. No significant differences in the duration of viral shedding were found in different gender, age (>2 vs. ≤2 years), and with or without underlying diseases groups. Viral shedding in children with severe HAdV pneumonia persisted, among which HAdV-7 lasted longer than 3 months and the viral load decreased slowly than HAdV-3.

2.
Comput Biol Chem ; 90: 107426, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33352501

RESUMO

INTRODUCTION: It is reported that LTF had a radiation resistance effect, and its expression in nasopharyngeal carcinoma (NPC) was significantly down-regulated. However, the mechanism of down-regulated LTF affecting the sensitivity of radiotherapy has remained elusive. METHODS: We re-analyzed the microarray data GSE36972 and GSE48503 to find differentially expressed genes (DEGs) in NPC cell line 5-8 F transfected with LTF or vector control, and the DEGs between radio-resistant and radio-sensitive NPC cell lines. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment and protein-protein interaction network (PPI) analysis of DEGs were performed to obtain the node genes. The target genes of miR-214 were also predicted to complement the mechanism associated with radiotherapy resistance because it could directly target LTF. RESULTS: This study identified 1190 and 1279 DEGs, respectively. GO and KEGG analysis showed that apoptotic process and proliferation, PI3K-Akt signaling pathway were significantly enriched pathways. Four nodes (DUSP1, PPARGC1A, FOS and SMARCA1) associated with LTF were screened. And 42 target genes of miR-214 were cross-linked to radiotherapy sensitivity. CONCLUSIONS: The present study demonstrates the possible molecular mechanism that the down-regulated LTF enhances the radiosensitivity of NPC cells through interaction with DUSP1, PPARGC1A, FOS and SMARCA1, and miR-214 as its superior negative regulator may play a role in regulating the radiotherapy effect.

3.
Biomed Pharmacother ; 134: 111103, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33338747

RESUMO

Nanomedicines offer nanoscale drug delivery system. They offer ways of promising drug transportation, and address the issues of lack of targeting and permeability of traditional drugs. The physical and chemical properties in the domain of nanomedicine applications in vivo have not been sufficiently delivered. What's more, the metabolic of nanomedicines is not clear enough. Those factors which mentioned above determine that many nanomedicines have not yet realized clinical application due to their safety problems and in vivo efficacy. For example, they may cause immune response and cytotoxicity, as well as the ability to clear organs in vivo, the penetration ability of them and the lack of targeting ability may also cause poor efficacy of drugs in vivo. In this review, the new progresses of different kinds of nanomedicines (including gold nanoparticles, nanorobots, black phosphorus nanoparticles, brain diseases, gene editing and immunotherapy etc.) in anti-tumor, antibacterial, ocular diseases and arteriosclerosis in recent years were summarized. Their shortcomings were pointed out, and the new methods to improve the biosafety and efficacy were summarized.

4.
Biomed Pharmacother ; 133: 111074, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33378973

RESUMO

In the era of big data, massive genetic data, as a new industry, has quickly swept almost all industries, especially the pharmaceutical industry. As countries around the world start to build their own gene banks, scientists study the data to explore the origins and migration of humans. Moreover, big data encourage the development of cancer therapy and bring good news to cancer patients. Big datum has been involved in the study of many diseases, and it has been found that analyzing diseases at the gene level can lead to more beneficial treatment options than ordinary treatments. This review will introduce the development of extensive data in medical research from the perspective of big data and tumor, neurological and psychiatric diseases, cardiovascular diseases, other applications and the development direction of big data in medicine.

5.
Entropy (Basel) ; 22(11)2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33286959

RESUMO

Crashes that involved large trucks often result in immense human, economic, and social losses. To prevent and mitigate severe large truck crashes, factors contributing to the severity of these crashes need to be identified before appropriate countermeasures can be explored. In this research, we applied three tree-based machine learning (ML) techniques, i.e., random forest (RF), gradient boost decision tree (GBDT), and adaptive boosting (AdaBoost), to analyze the factors contributing to the severity of large truck crashes. Besides, a mixed logit model was developed as a baseline model to compare with the factors identified by the ML models. The analysis was performed based on the crash data collected from the Texas Crash Records Information System (CRIS) from 2011 to 2015. The results of this research demonstrated that the GBDT model outperforms other ML methods in terms of its prediction accuracy and its capability in identifying more contributing factors that were also identified by the mixed logit model as significant factors. Besides, the GBDT method can effectively identify both categorical and numerical factors, and the directions and magnitudes of the impacts of the factors identified by the GBDT model are all reasonable and explainable. Among the identified factors, driving under the influence of drugs, alcohol, and fatigue are the most important factors contributing to the severity of large truck crashes. In addition, the exists of curbs and medians and lanes and shoulders with sufficient width can prevent severe large truck crashes.

6.
Biomed Pharmacother ; 135: 111173, 2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33383370

RESUMO

Imaging genomics refers to the establishment of the connection between invasive gene expression features and non-invasive imaging features. Tumor imaging genomics can not only understand the macroscopic phenotype of tumor, but also can deeply analyze the cellular and molecular characteristics of tumor tissue. In recent years, tumor imaging genomics has been a key in the field of medicine. The incidence of cancer in China has increased significantly, which is the main reason of disease death of urban residents. With the rapid development of imaging medicine, depending on imaging genomics, many experts have made remarkable achievements in tumor screening and diagnosis, prognosis evaluation, new treatment targets and understanding of tumor biological mechanism. This review analyzes the relationship between tumor radiology and gene expression, which provides a favorable direction for clinical staging, prognosis evaluation and accurate treatment of tumors.

7.
Huan Jing Ke Xue ; 41(8): 3748-3757, 2020 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124350

RESUMO

In order to explore the conjugation of genes encoding extended-spectrum ß-lactamase (ESBL), ESBL-expressing P. aeruginosa and E.coli strains isolated from the wastewater of major hospitals in Singapore were used as donors. gfp-tagged E.coli SCC1 strains resistant to chloramphenicol (CHL) were chosen as recipients. Using response surface analysis, we detected and analyzed the induction of conjugal transfer under single-exposure and co-exposure of tetracycline (TC), sulfamethoxazole (SMZ), and ceftazidime (CAZ) at sublethal concentrations. It was found that the ESBL plasmid could be conjugal transferred from P. aeruginosa and E.coli strains to the recipient E.coli SCC1 strains at an average frequency of 0.0015 and 0.0042, respectively, without stress from inducing antibiotics, thus showing a low fitness cost and higher conjugal frequency between E.coli strains under the exposure of sub-MIC antibiotics. A significant conjugation between E.coli strains occurred under the single-exposure or co-exposure of a TC concentration of <0.03 mg·L-1 and a CAZ concentration of <0.002 mg·L-1, as inhibited by a sub-MIC level of TC. The conjugation between P. aeruginosa and E.coli strains was stimulated under the exposure of TC and CAZ with concentrations 5-times larger than the MIC, while no significant induction was detected from the sub-MIC antibiotics.


Assuntos
Antibacterianos , Transferência Genética Horizontal , Antibacterianos/toxicidade , Ceftazidima , Escherichia coli/genética , Plasmídeos/genética , beta-Lactamases/genética
8.
Part Fibre Toxicol ; 17(1): 50, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008402

RESUMO

BACKGROUND: The biosafety concern of silica nanoparticles (SiNPs) is rapidly expanding alongside with its mass production and extensive applications. The cardiovascular effects of SiNPs exposure have been gradually confirmed, however, the interaction between SiNPs exposure and atherosclerosis, and the underlying mechanisms still remain unknown. Thereby, this study aimed to explore the effects of SiNPs on the progression of atherosclerosis, and to investigate related mechanisms. RESULTS: We firstly investigated the in vivo effects of SiNPs exposure on atherosclerosis via intratracheal instillation of ApoE-/- mice fed a Western diet. Ultrasound microscopy showed a significant increase of pulse wave velocity (PWV) compared to the control group, and the histopathological investigation reflected a greater plaque burden in the aortic root of SiNPs-exposed ApoE-/- mice. Compared to the control group, the serum levels of total triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) were elevated after SiNPs exposure. Moreover, intensified macrophage infiltration and endoplasmic reticulum (ER) stress was occurred in plaques after SiNPs exposure, as evidenced by the upregulated CD68 and CHOP expressions. Further in vitro, SiNPs was confirmed to activate ER stress and induce lipid accumulation in mouse macrophage, RAW264.7. Mechanistic analyses showed that 4-PBA (a classic ER stress inhibitor) pretreatment greatly alleviated SiNPs-induced macrophage lipid accumulation, and reversed the elevated CD36 expression induced by SiNPs. CONCLUSIONS: Our results firstly revealed the acceleratory effect of SiNPs on the progression of atherosclerosis in ApoE-/- mice, which was related to lipid accumulation caused by ER stress-mediated upregulation of CD36 expression in macrophage.

9.
PLoS One ; 15(10): e0238789, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33021994

RESUMO

The value of ecosystem services is affected by increasing human activities. However, the anthropogenic driving mechanisms of ecosystem services are poorly understood. Here, we established a deep learning model to approximate the ecosystem service value (ESV) of Nanjing City using 23 socioeconomic factors. A multi-view analysis was then conducted on feasible impact mechanisms using model disassembly. The results indicated that certain factors had their own significant and independent effects on ESV, such as the proportion of water areas in the land-use structure and the output value of the secondary industry. The proportion of ecological water should be increased as much as possible, whereas the output value of the secondary industry should be reasonably controlled in Nanjing. Other intrinsically related factors were likely to be composited together to affect ESV, such as industrial water consumption and industrial electricity consumption. In Nanjing, simultaneously optimizing socio-economic factors related to city size, resources, and energy use efficiency likely represents an effective management strategy for maintaining and enhancing regional ecological service capabilities. The results of this work suggest that deep learning is an effective method of deepening studies on the prediction of ESV trends and human-driven mechanisms.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Atividades Humanas , China , Cidades , Aprendizado Profundo , Humanos , Fatores Socioeconômicos
10.
Oxid Med Cell Longev ; 2020: 9815039, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014281

RESUMO

Aims: We aimed to investigate whether LCZ696 protects against pathological cardiac hypertrophy by regulating the Sirt3/MnSOD pathway. Methods: In vivo, we established a transverse aortic constriction animal model to establish pressure overload-induced heart failure. Subsequently, the mice were given LCZ696 by oral gavage for 4 weeks. After that, the mice underwent transthoracic echocardiography before they were sacrificed. In vitro, we introduced phenylephrine to prime neonatal rat cardiomyocytes and small-interfering RNA to knock down Sirt3 expression. Results: Pathological hypertrophic stimuli caused cardiac hypertrophy and fibrosis and reduced the expression levels of Sirt3 and MnSOD. LCZ696 alleviated the accumulation of oxidative reactive oxygen species (ROS) and cardiomyocyte apoptosis. Furthermore, Sirt3 deficiency abolished the protective effect of LCZ696 on cardiomyocyte hypertrophy, indicating that LCZ696 induced the upregulation of MnSOD and phosphorylation of AMPK through a Sirt3-dependent pathway. Conclusions: LCZ696 may mitigate myocardium oxidative stress and apoptosis in pressure overload-induced heart failure by regulating the Sirt3/MnSOD pathway.

11.
BMC Urol ; 20(1): 136, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867742

RESUMO

BACKGROUND: Calcium oxalate monohydrate (COM), the major crystalline composition of most kidney stones, induces inflammatory infiltration and injures in renal tubular cells. However, the mechanism of COM-induced toxic effects in renal tubular cells remain ambiguous. The present study aimed to investigate the potential changes in proteomic landscape of proximal renal tubular cells in response to the stimulation of COM crystals. METHODS: Clinical kidney stone samples were collected and characterized by a stone component analyzer. Three COM-enriched samples were applied to treat human proximal tubular epithelial cells HK-2. The proteomic landscape of COM-crystal treated HK-2 cells was screened by TMT-labeled quantitative proteomics analysis. The differentially expressed proteins (DEPs) were identified by pair-wise analysis. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of DEPs were performed. Protein interaction networks were identified by STRING database. RESULTS: The data of TMT-labeled quantitative proteomic analysis showed that a total of 1141 proteins were differentially expressed in HK-2 cells, of which 699 were up-regulated and 442 were down-regulated. Functional characterization by KEGG, along with GO enrichments, suggests that the DEPs are mainly involved in cellular components and cellular processes, including regulation of actin cytoskeleton, tight junction and focal adhesion. 3 high-degree hub nodes, CFL1, ACTN and MYH9 were identified by STRING analysis. CONCLUSION: These results suggested that calcium oxalate crystal has a significant effect on protein expression profile in human proximal renal tubular epithelial cells.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32899687

RESUMO

Displaced left-turn (DLT) intersections are designed to increase the mobility of vehicles by relocating the left-turn lane (lanes) to the far-left side of the road upstream of the main signalized intersection. Since DLT is a relatively new design and very limited crash data are available, previous studies have focused mainly on the analysis of its operational performance rather than its safety performance. To fill this gap, in this study, we investigated the safety performance of two DLT intersections located in San Marcos, Texas. Crash data from 2011 to April 2018 were extracted from the TxDOT Crash Record Information System (CRIS). These crash data were analyzed using two different approaches, i.e., statistical analysis and collision diagram-based analysis. The results of this study indicated that DLT did not increase the overall crash frequencies at the studied intersections. Traffic crashes related to left turns and right turns were reduced significantly by DLT. Meanwhile, it also caused safety issues related to traffic signage, traffic signal, geometric design, and access management at DLT intersections. Thus, in the implementation of DLT intersections, traffic engineers need to carefully consider different aspects of the DLT intersection design, including access management, traffic signal coordination, and driver acceptance. As a result of these analyses, recommendations were provided for the safe implementation of the DLT design in the future.

13.
Stem Cell Res ; 48: 101932, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32889247

RESUMO

Familial exudative vitreoretinopathy (FEVR) is an autosomal dominant genetic disease. An induced pluripotent stem cell line (EHTJUi002-A) was generated from umbilical cord blood mononuclear cells (UCBMCs) of a neonate with heterozygous mutation of p.W226X(c.678G>A) in the FZD4 gene. This iPSC model offers a very valuable resource to study the pathological mechanism of FEVR in vitro.

14.
J Investig Med ; 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32928904

RESUMO

This study aims to evaluate the potential of percutaneous patent foramen ovale (PFO) closure to improve the headache in patients with migraine and PFO, and discuss the difference between the randomized controlled trials (RCTs) and the single-center studies. Patients of migraine with a large shunt of PFO, who experienced ≥2 headache attacks per month and failed ≥2 categories of standardized medication, underwent PFO closure in First Affiliated Hospital of Xi'an Jiao Tong University. The clinical outcomes, including frequency and duration of headache attacks, Headache Impact Test (HIT-6) score, and Visual Analogue Scale (VAS) score, were evaluated at 3, 6, and 12 months of follow-up after the PFO closure. The different efficacies of the clinical outcomes between patients with and without aura as well as different grades of PFO were also evaluated, respectively. 134 patients with migraine (39 male and 95 female) with PFO were enrolled, whose average age was 39.21±11.37 years. After PFO closure, there was a significant reduction in frequency and duration of headache attacks, HIT-6 score, and VAS score at 3, 6, and 12 months' follow-up (p<0.001). Migraine was completely relieved in 54 (40.30%) patients during 12 months' follow-up. The frequency of migraine was reduced by >50% in 44 (32.84%) patients at 3 months' follow-up and increased to 48 (35.82%) at 12 months' follow-up. 31.03% patients remained residual shunt after 6 months of closure with varying improvements of headache. This study confirmed that PFO closure can effectively reduce frequency and duration of migraine and improve quality of life, but the definitive indications and long-term effect still need further research.

15.
J Safety Res ; 74: 109-117, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32951771

RESUMO

INTRODUCTION: Due to their size and weight, trucks require more space and time to make left turns when exiting or entering a roadway. Therefore, appropriate median treatments are critical for roadways with substantial truck traffic. The two-way left-turn lane (TWLTL) and raised median (RM) are the two types of median most commonly used to improve roadway mobility and manage roadway accessibility. However, previous studies on these median treatments have focused primarily on the general traffic conditions and geometric roadway features without considering the truck traffic impact. METHOD: To fill this gap, this study investigates the truck impacts on TWLTL and RM by considering two major influencing factors - truck percentage and roadway access point density. First, a negative binomial regression is developed to analyze the relationship between crash frequency and various influencing factors. Next, the crash rate difference analysis between the TWLTL and RM is conducted to identify critical points for these two factors. RESULTS: The findings indicate that, compared with RM, TWLTL has significantly higher crash frequency, especially for roadways with a higher percentage of trucks. This suggests that the percentage of trucks should be taken into consideration when selecting an appropriate type of roadway median.

16.
PLoS Biol ; 18(9): e3000825, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32886690

RESUMO

Microbial dysbiosis in the upper digestive tract is linked to an increased risk of esophageal squamous cell carcinoma (ESCC). Overabundance of Porphyromonas gingivalis is associated with shorter survival of ESCC patients. We investigated the molecular mechanisms driving aggressive progression of ESCC by P. gingivalis. Intracellular invasion of P. gingivalis potentiated proliferation, migration, invasion, and metastasis abilities of ESCC cells via transforming growth factor-ß (TGFß)-dependent Drosophila mothers against decapentaplegic homologs (Smads)/Yes-associated protein (YAP)/Transcriptional coactivator with PDZ-binding motif (TAZ) activation. Smads/YAP/TAZ/TEA domain transcription factor1 (TEAD1) complex formation was essential to initiate downstream target gene expression, inducing an epithelial-mesenchymal transition (EMT) and stemness features. Furthermore, P. gingivalis augmented secretion and bioactivity of TGFß through glycoprotein A repetitions predominant (GARP) up-regulation. Accordingly, disruption of either the GARP/TGFß axis or its activated Smads/YAP/TAZ complex abrogated the tumor-promoting role of P. gingivalis. P. gingivalis signature genes based on its activated effector molecules can efficiently distinguish ESCC patients into low- and high-risk groups. Targeting P. gingivalis or its activated effectors may provide novel insights into clinical management of ESCC.


Assuntos
Infecções por Bacteroidaceae/complicações , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Porphyromonas gingivalis/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Animais , Infecções por Bacteroidaceae/metabolismo , Infecções por Bacteroidaceae/mortalidade , Infecções por Bacteroidaceae/patologia , Células Cultivadas , Progressão da Doença , Drosophila , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/microbiologia , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/microbiologia , Carcinoma de Células Escamosas do Esôfago/mortalidade , Feminino , Seguimentos , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Transdução de Sinais/fisiologia , Proteínas Smad/metabolismo , Análise de Sobrevida , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo
17.
Regen Med ; 15(6): 1735-1747, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32811280

RESUMO

Aim: We aimed to evaluate the capacity of the bilayer polylactic-co-glycolic acid (PLGA)/TGF-ß3/adipose-derived mesenchymal stem cell (ADSC) construct used to repair cartilage defects and the role of ADSCs in the repair process in vivo. Materials & methods: Defects were created surgically on the femoropatellar groove of knee joints in 64 rabbits. All the rabbits were randomly divided into four groups: defect group, PLGA group, PLGA/TGF-ß3 group and PLGA/TGF-ß3/ADSC group. In vivo MRI and Prussian blue staining were applied. Quantitative real-time PCR and western blot methods were used to analyze the gene and protein expression. Results & conclusion: The result showed that TGF-ß3 could effectively stimulate the expressions of aggrecan, collagen type II and SRY-related HMG box 9 (SOX9). The bilayer PLGA/TGF-ß3/ADSC construct showed a promising repair effect.

18.
Neuroimage ; 222: 117274, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32818613

RESUMO

Genome-wide association studies have demonstrated significant links between human brain structure and common DNA variants. Similar studies with rodents have been challenging because of smaller brain volumes. Using high field MRI (9.4 T) and compressed sensing, we have achieved microscopic resolution and sufficiently high throughput for rodent population studies. We generated whole brain structural MRI and diffusion connectomes for four diverse isogenic lines of mice (C57BL/6J, DBA/2J, CAST/EiJ, and BTBR) at spatial resolution 20,000 times higher than human connectomes. We measured narrow sense heritability (h2) I.e. the fraction of variance explained by strains in a simple ANOVA model for volumes and scalar diffusion metrics, and estimates of residual technical error for 166 regions in each hemisphere and connectivity between the regions. Volumes of discrete brain regions had the highest mean heritability (0.71 ± 0.23 SD, n = 332), followed by fractional anisotropy (0.54 ± 0.26), radial diffusivity (0.34 ± 0.022), and axial diffusivity (0.28 ± 0.19). Connection profiles were statistically different in 280 of 322 nodes across all four strains. Nearly 150 of the connection profiles were statistically different between the C57BL/6J, DBA/2J, and CAST/EiJ lines. Microscopic whole brain MRI/DTI has allowed us to identify significant heritable phenotypes in brain volume, scalar DTI metrics, and quantitative connectomes.

19.
Environ Int ; 144: 106030, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798800

RESUMO

Increasing ozone concentrations are becoming a severe problem for air pollution in China and have an adverse impact on human health. Here we evaluate premature deaths attributable to long-term exposure to ambient ozone in China between 2013 and 2017 with an air quality model at 5 km resolution and the latest estimates of the relative risk to health. We use a modified inverse distance weighting method to bias-correct the key model-simulated ozone metrics. We find that on a 5-year average basis there are 186,000 (95% Confidence Interval: 129,000-237,000) respiratory deaths and 125,000 (42,000-204,000) cardiovascular deaths attributable to ozone exposure. Sichuan exhibits the largest per capita respiratory mortality (0.31‰) among all provinces. We find that there are 73,000 (51,000-93,000) premature respiratory deaths in urban areas, accounting for 39% of total deaths. Between 2013 and 2017 the population-weighted annual average maximum daily 8-h average ozone (AMDA8) and premature respiratory deaths increased by 14% and 31%, respectively, at a national level. Changes in precursor emissions explain most of these increases, with differences in meteorology accounting for 21% and 16% respectively. Interannual variations in population-weighted ozone and premature respiratory deaths at a provincial level are much larger than those at a national level, particularly in northern, central and eastern China. These findings emphasize that ozone should be an important focus of future air quality policies in China, and tighter controls of precursor emissions are urgently needed.

20.
Plant Physiol ; 184(2): 923-932, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32796091

RESUMO

Photoperiod- and thermosensitive genic male sterility (P/TGMS) lines are widely used in crop breeding. The fertility conversion of Arabidopsis (Arabidopsis thaliana) TGMS lines including cals5-2, which is defective in callose wall formation, relies on slow development under low temperatures. In this study, we discovered that cals5-2 also exhibits PGMS. Fertility of cals5-2 was restored when pollen development was slowed under short-day photoperiods or low light intensity, suggesting that slow development restores the fertility of cals5-2 under these conditions. We found that several other TGMS lines with defects in pollen wall formation also exhibited PGMS characteristics. This similarity indicates that slow development is a general mechanism of PGMS fertility restoration. Notably, slow development also underlies the fertility recovery of TGMS lines. Further analysis revealed the pollen wall features during the formation of functional pollens of these P/TGMS lines under permissive conditions. We conclude that slow development is a general mechanism for fertility restoration of P/TGMS lines and allows these plants to take different strategies to overcome pollen formation defects.

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