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1.
Nat Struct Mol Biol ; 27(2): 179-191, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32042152

RESUMO

Long interspersed element-1 (LINE-1, or L1) is the only autonomous retrotransposon that is active in human cells. Different host factors have been shown to influence L1 mobility; however, systematic analyses of these factors are limited. Here, we developed a high-throughput microscopy-based retrotransposition assay that identified the double-stranded break (DSB) repair and Fanconi anemia (FA) factors active in the S/G2 phase as potent inhibitors and regulators of L1 activity. In particular, BRCA1, an E3 ubiquitin ligase with a key role in several DNA repair pathways, directly affects L1 retrotransposition frequency and structure and plays a distinct role in controlling L1 ORF2 protein translation through L1 mRNA binding. These results suggest the existence of a 'battleground' at the DNA replication fork between homologous recombination (HR) factors and L1 retrotransposons and reveal a potential role for L1 in the genotypic evolution of tumors characterized by BRCA1 and HR repair deficiencies.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31897702

RESUMO

PURPOSE: To investigate the clinical features and spectral-domain optical coherence tomography (SD-OCT) findings of retinal astrocytic hamartoma (RAH) in Chinese patients with tuberous sclerosis complex (TSC). METHODS: The medical records of 91 consecutive patients with established TSC diagnosis were retrospectively reviewed. Fundus findings regarding RAH documented by fundus photography and SD-OCT at presentation were collected and analyzed. RESULTS: RAHs were seen in 69 of the 91 patients (75.8%); 50.7% of these patients showed bilateral retinal involvement. Type 1 RAH was found the most common type with a prevalence of 94.2%, while type 2 and type 3 RAH with 7.2% and 18.8% respectively. A significant correlation between age and RAH types was shown by Fisher's exact test (p < 0.001). By SD-OCT, non-calcified RAHs featured in hyperreflective thickening of the retinal nerve fiber layer with some degree of retinal disorganization, while multinodular calcified RAHs characterized with moth-eaten appearances representing intraretinal calcification with posterior dense optical shadowing. CONCLUSION: A higher prevalence of TSC-associated RAH but an unexpected lower prevalence of calcified RAHs was shown in Chinese compared with that of Caucasians. SD-OCT can be used to facilitate the detection and follow-up of RAHs.

3.
J Diabetes ; 12(1): 10-20, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31170331

RESUMO

BACKGROUND: This study investigated the association between birth weight and diabetes in a Chinese population, and the effects of body mass index (BMI) and lifestyle factors in later life on this association. METHODS: Data from 49 118 participants aged ≥40 years with recalled birth weight from the Risk Evaluation of cAncers in Chinese diabeTic Individuals: a lONgitudinal (REACTION) study, a nationwide population-based cohort, were used. Diabetes diagnosis was based on oral glucose tolerance tests and HbA1c measurements. Logistic regression models were used to evaluate the association of birth weight and risk of diabetes in later life. RESULTS: Increased risk of diabetes was associated with lower or higher birth weight. Compared with individuals with a birth weight of 2500 to 3499 g, the odds ratios (ORs) and 95% confidence intervals (CIs) of diabetes for individuals with a birth weight of <2500, between 3500 and 3999, and ≥4000 g were 1.28 (1.11-1.47), 1.11 (1.04-1.19), and 1.20 (1.07-1.34), respectively. Significant associations were prominent in participants with a current BMI ≥24 kg/m2 , but not detected in those with a normal BMI (OR 1.20 [95% CI 0.96-1.49], 1.11 [95% CI 0.98-1.25], and 1.10 [95% CI 0.89-1.37], respectively). Moreover, there was no increased risk of diabetes in individuals with a low birth weight but with healthy dietary habits (OR 0.94; 95% CI 0.68-1.29) or ideal physical activity (OR 1.41; 95% CI 0.97-2.04). CONCLUSIONS: A U-shaped association was observed between birth weight and the risk of diabetes. Healthy lifestyles (healthy dietary habits or ideal physical activity) may eliminate the negative effects of low birth weight in the development of diabetes, but not the effect of high birth weight.

4.
Ecotoxicol Environ Saf ; 190: 110044, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31869717

RESUMO

Low-energy shock waves (LESWs) have been widely used in the intervention of a subset of diseased tissues and organs with good results. However, it is unclear whether they can be used directly to intervene in the testes. Therefore, the aim of this study was to determine a relatively safe energy density and impulse number for rat testes. A total of 176 male rats were randomly and equally assigned to different intervention groups. Among them, 144 rats were assigned to 18 shock subgroups with different energy densities (0.02, 0.04 and 0.06 mJ/mm2), different impulse numbers (500, 1000 and 1500 impulses) and different shock periods (2 and 8 weeks). The remaining 32 rats were divided into the sham intervention (S) groups and the blank control (N) groups with observation periods of 2 weeks and 8 weeks. One day after the last LESWs intervention, all the rats were weighed, and the concentrations of reproductive endocrine hormones were measured, the semen quality and testicular tissue oxidative stress levels were analyzed, and histomorphology and ultrastructures were observed. We found that there were no significant differences in the whole-body physiological state, testicular tissue morphology, oxidative stress state and sperm quality between the L1 shock group and the corresponding S group and N group (all p˃0.05, respectively). However, the other parameters of the shock groups caused different degrees of damage to the structure and function of rat testes, and the whole-body physiological state was also adversely affected. This study demonstrated that LESWs with an energy density of 0.02 mJ/mm2 and 500 impulses had no adverse effects on the rat testes.

5.
Sci Total Environ ; 698: 133860, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514029

RESUMO

The correlation between long-term exposure to SRF-EMR and the decline in male fertility is gradually receiving increasing attention from the medical society. While male reproductive organs are often exposed to SRF-EMR, little is currently known about the direct effects of long-term SRF-EMR exposure on the testes and its involvement in the suppression of male reproductive potential. The present study was designed to investigate this issue by using 4G SRF-EMR in rats. A unique exposure model using a 4G smartphone achieved localized exposure to the scrotum of the rats for 6 h each day (the smartphone was kept on active talk mode and received an external call for 1 min over 10 min intervals). Results showed that SRF-EMR exposure for 150 days decreased sperm quality and pup weight, accompanied by testicular injury. However, these adverse effects were not evident in rats exposed to SRF-EMR for 50 days or 100 days. Sequencing analysis and western blotting suggested Spock3 overexpression in the testes of rats exposed to SRF-EMR for 150 days. Inhibition of Spock3 overexpression improved sperm quality decline and alleviated testicular injury and BTB disorder in the exposed rats. Additionally, SRF-EMR exposure suppressed MMP2 activity, while increasing the activity of the MMP14-Spock3 complexes and decreasing MMP14-MMP2 complexes; these results were reversed by Spock3 inhibition. Thus, long-term exposure to 4G SRF-EMR diminished male fertility by directly disrupting the Spock3-MMP2-BTB axis in the testes of adult rats. To our knowledge, this is the first study to show direct toxicity of SRF-EMR on the testes emerging after long-term exposure.


Assuntos
Radiação Eletromagnética , Smartphone , Testículo/efeitos da radiação , Animais , Masculino , Ondas de Rádio , Ratos , Reprodução
6.
Mar Drugs ; 17(12)2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31835446

RESUMO

Active polysaccharides as safe and natural polymers against bacterial diarrhea have been reconsidered as an alternative to antibiotics. This work investigated the inhibiting effect of depolymerized sulfated galactans from Eucheuma serra and Gracilaria verrucosa on the growth and adhesion of diarrheagenic enterotoxigenic Escherichia coli (ETEC) K88. Results showed that the sulfated polysaccharides with molecular weight distribution ≤20.0 kDa exhibited antibacterial activity against ETEC K88. A structure-activity study revealed that the anti-ETEC K88 activity of sulfated polysaccharides is strictly determined by their molecular weight distribution, sulfate group content, and monosaccharide composition. In addition, the promoted nucleic acid release and the fluorescence quenching of membrane proteins were observed after the treatment with selected polysaccharides. Scanning electron microscopy further confirmed that the depolymerized sulfated galactans can effectively inhibit ETEC K88 adhesion. In conclusion, depolymerized sulfated galactans exhibited an inhibitory effect on the growth and adhesion of ETEC K88.

7.
Sci Rep ; 9(1): 17796, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31780777

RESUMO

The South China Sea hosts a wide range of aerosol pollutants with the uneven development of socio-economic and complicated meteorology system. To fill the gap of the maritime aerosol characteristics over the sea, we selected the multi-year ground-based measurements of Taiping Site and Dongsha Site to investigate the optical and microphysical properties. In Taiping, the vast majority of aerosol optical depths (AODs) are less than 0.2, but that of Dongsha shows the wider distribution of AODs from 0 to 0.6. Angstrom Exponent frequency distribution in Taiping peaks at the range of 0.75-1.25 but that has the left-skewed distribution in Taiping Island. Moreover, there is a variation in the coarse-mode volume concentration in Taiping Island but less variation in the fine mode. The seasonal maritime aerosol properties of Taiping and Dongsha have been analyzed that can be employed as a maritime look up table (LUT) kernel in coupled atmospheric retrieval and correction algorithms.

8.
BMC Ophthalmol ; 19(1): 232, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752754

RESUMO

BACKGROUND: To report a case of Purtscher-like retinopathy (PUR) and the optical coherence tomography (OCT) and OCT angiography (OCT-A) findings before and after treatment. CASE PRESENTATION: A 65-year-old male presented with acute onset of vision loss for 2 weeks. Fundus examination revealed cotton-wool spots, retinal haemorrhage, and Purtscher flecken spread around the optic disc in the right eye. He was diagnosed with Purtscher-like retinopathy because he lacked any traumatic medical history. OCT presented some band-like hyperreflective lesions at the inner nuclear layer, which are indicative of paracentral acute middle maculopathy (PAMM). OCT-A revealed apparent reduction in blood flow signal at the deep retina and choriocapillaris layers with a honeycomb-like hypointense signal pattern. After 3 months of follow-up, OCT revealed resolution of retinal oedema, but PAMM lesions remained visible. Based on OCT-A, the honeycomb-like pattern turned into a homogeneous reduction in blood flow with small patches of hypointense signal areas in the choriocapillaris. CONCLUSION: This case presented a new OCT-A sign in PUR with a honeycomb-like hypointense signal at the choriocapillaris layer, indicating the involvement and ischaemia of the choroid during the pathological process.

9.
ACS Appl Mater Interfaces ; 11(46): 43452-43459, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31659892

RESUMO

Two-dimensional (2D)/three-dimensional (3D) perovskites have been successfully applied in high-efficiency light-emitting diodes (LEDs) because of their large exciton binding energy (Eb) caused by the quantum and dielectric confinements. Thermal annealing and antisolvent treatments are usually executed in order to promote the crystallization and film quality of perovskites, which add complexity to the device fabrication process. Here, the cesium-based 2D/3D perovskite was prepared by introducing ammonium halide benzamidine hydrochloride (BMCl) as the additive. By further introducing an appropriate amount of MABr and PbBr2, BM2(Cs1-xMAxPbBr3)n-1PbBr4 crystals can be formed rapidly without any additional treatments, while inhibiting the formation of the unfavorable Cs4PbBr6 phase. The optimized 2D/3D perovskite-based LEDs achieved a maximum luminance of 12 367 Cd/m2, a current efficiency of 17.4 Cd/A, and an external quantum efficiency of 5.2%. Our results suggest that appropriate perovskite crystallization can be achieved at room temperature by the regulation of precursor solution, making the perovskite crystallization process easier to control with reduced processing complexity.

10.
ACS Appl Mater Interfaces ; 11(39): 35827-35834, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31507160

RESUMO

An in situ spectroscopy ellipsometry technique is utilized to probe the molecular ordering sequences of PBDB-T-2F/IT-4F/COi8DFIC ternary photovoltaic blends fabricated by bar-coating in air. The time-resolved dynamics show that the primary electron acceptor IT-4F aggregates ahead of the secondary acceptor COi8DFIC in the bar-coated photoactive layer, although the latter has much stronger crystallization ability. Wetting coefficient analysis supports that COi8DFIC locates at the interface between the host components PBDB-T-2F and IT-4F. We demonstrate that the suitable degree of phase separation with the presence of 20 wt % COi8DFIC facilitates exciton dissociation and charge transfer, leading to a remarkable power conversion efficiency of 13.2% as well as excellent stability of ternary organic solar cells (OSCs), which is among the highest reported efficiency for OSCs that were fabricated by scalable solution-casting in ambient conditions.

11.
ACS Appl Mater Interfaces ; 11(41): 37833-37841, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31538760

RESUMO

Perovskite solar cells (PSCs) have demonstrated encouraging progress in recent years. Additive engineering, where diverse additives are incorporated into the perovskite layer, has been widely adopted to tune the perovskite grains, reduce defect density and charge recombination. Here, we observe a universal phenomenon that organic chloride additives enhance the open circuit voltage (VOC) and power conversion efficiencies (PCEs) of direct PSCs but decrease the VOC, short-circuit current (JSC), and PCE of inverted PSCs, regardless of the choice of charge transport materials. The polyTPD-based direct device incorporating trimethylammonium chloride (TACl) additive delivery improved PCE from 17.8 to 20.0%, arising from the enhanced VOC from 1.03 to 1.12 V. With the same content of TACl, the best PCE of the polyTPD-based inverted device decreased from 20.2 to 18.5% because of the reduced VOC (1.05-1.01 V) and JSC (23.2-22.5 mA/cm2). Our investigation confirms that organic chloride will p-dope perovskites and elevate the work functions, which lead to favorable/unfavorable charge transfer between perovskite films and its upper transport layers in direct and inverted devices. This work provides an insight into the rational design of the device structure when applying additives which can dope the perovskite to affect charge transfer at the perovskite/charge transport layer interface.

12.
Nanomedicine (Lond) ; 14(17): 2339-2353, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31414945

RESUMO

Aim: Biomarker-targeted nanocarrier holds promise for early diagnosis and effective therapy of cancer. Materials & methods: This work successfully designs and evaluates GPC1-targeted, gemcitabine (GEM)-loaded multifunctional gold nanocarrier for near-infrared fluorescence (NIRF)/MRI and targeted chemotherapy against pancreatic cancer in vitro and in vivo. Results: Blood biochemical and histological analyses show that the in vivo toxicity of GPC1-GEM-nanoparticles (NPs) was negligible. Both in vitro and in vivo studies demonstrate that GPC1-GEM-NPs can be used as NIRF/MR contrast agent for pancreatic cancer detection. Treatment of xenografted mice with GPC1-GEM-NPs shows a higher tumor inhibitory effect compared with controls. Conclusion: This novel theranostic nanoplatform provides early diagnostic and effective therapeutic potential for pancreatic cancer.

13.
JAMA Cardiol ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31365039

RESUMO

Importance: Whether optimal cardiovascular health metrics may counteract the risk of cardiovascular events among patients with prediabetes or diabetes is unclear. Objective: To investigate the associations of ideal cardiovascular health metrics (ICVHMs) with subsequent development of cardiovascular disease (CVD) among participants with prediabetes or diabetes as compared with participants with normal glucose regulation. Design, Setting, and Participants: The China Cardiometabolic Disease and Cancer Cohort Study was a nationwide, population-based, prospective cohort study of 20 communities from various geographic regions in China. The study included 111 765 participants who were free from CVD or cancer at baseline. Data were analyzed between 2011 and 2016. Exposures: Prediabetes and diabetes were defined according to the American Diabetes Association 2010 criteria. Seven ICVHMs were adapted from the American Heart Association recommendations. Main Outcomes and Measures: The composite of incident fatal or nonfatal CVD, including cardiovascular death, myocardial infarction, stroke, and hospitalized or treated heart failure. Results: Of the 111 765 participants, 24 881 (22.3%) had normal glucose regulation, 61 024 (54.6%) had prediabetes, and 25 860 (23.1%) had diabetes. Mean (SD) age ranged from 52.9 (8.6) years to 59.4 (8.7) years. Compared with participants with normal glucose regulation, among participants with prediabetes, the multivariable-adjusted hazard ratio for CVD was 1.34 (95% CI, 1.16-1.55) for participants who had 1 ICVHM or less and 0.57 (95% CI, 0.43-0.75) for participants who had at least 5 ICVHMs; among participants with diabetes, the hazard ratios for CVD were 2.05 (95% CI, 1.76-2.38) and 0.80 (95% CI, 0.56-1.15) for participants who had 1 ICVHM or less and at least 5 ICVHMs, respectively. Such pattern of association between ICVHM and CVD was more prominent for participants younger than 55 years (prediabetes and at least 5 ICVHMs: hazard ratio [HR], 0.32; 95% CI, 0.16-0.63; 1 ICVHM or less: HR, 1.58, 95% CI, 1.13-2.21; diabetes and at least 5 ICVHMs: HR, 0.99; 95% CI, 0.44-2.26; 1 ICVHM or less: HR, 2.46; 95% CI, 1.71-3.54; compared with normal glucose regulation) than for participants 65 years or older (prediabetes and at least 5 ICVHMs: HR, 0.80; 95% CI, 0.50-1.26; 1 ICVHM or less: HR, 1.01; 95% CI, 0.79-1.31; diabetes and at least 5 ICVHMs: HR, 0.79; 95% CI, 0.46-1.35; 1 ICVHM or less: HR, 1.73; 95% CI, 1.36-2.22, compared with normal glucose regulation; P values for interaction ≤.02). Additionally, the hazard ratio for CVD per additional ICVHM was 0.82 (95% CI, 0.79-0.86) among participants with prediabetes and was 0.85 (95% CI, 0.80-0.89) among participants with diabetes. Conclusions and Relevance: Participants with prediabetes or diabetes who had 5 or more ICVHMs exhibited lower or no significant excess CVD risks compared with the participants with normal glucose regulation.

14.
Nanomaterials (Basel) ; 9(7)2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31261670

RESUMO

With the developments in high-performance nano-insulation material technology, theoretical studies on the heat transfer mechanisms in these materials have been conducted. However, the conductivity of nanometer-sized skeletons is still unclear. It is necessary to clarify the thermal conductivity of nanometer-sized solid skeletons in order to better understand the heat transfer mechanisms in nano-insulation materials. In the present study, a theoretical model for the thermal conductivity of nanometer-sized skeletons in nano-insulation materials is presented based upon the meso-structure of the material and the equation of phonon transfer. The size effect in thermal conductivity of the nanometer-sized particles is studied numerically, and the thermal conductivity is theoretically obtained. At the same time, a reverse method is established for the thermal conductivity of nanometer-sized particles based on the method of particle swarm optimization (PSO). The skeleton thermal conductivity for a specific nano-insulation material with a density of 110 kg/m3 and porosity of 0.94 is identified based upon experimental data from literature. Comparison results show that the theoretical conductivity of nanometer-sized skeletons and the identified results give the values of 0.145 and 0.124 W/(m K), respectively, clearly revealing obvious an size effect in the thermal conductivity of nanometer-sized skeletons.

15.
Sensors (Basel) ; 19(13)2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31288478

RESUMO

Sensor fault detection and diagnosis (FDD) has great significance for ensuring the energy saving and normal operation of the air conditioning system. Chiller systems serving as an important part of central air conditioning systems are the major energy consumer in commercial and industrial buildings. In order to ensure the normal operation of the chiller system, virtual sensors have been proposed to detect and diagnose sensor faults. However, the performance of virtual sensors could be easily impacted by abnormal data. To solve this problem, virtual sensors combined with the maximal information coefficient (MIC) and a long short-term memory (LSTM) network is proposed for chiller sensor fault diagnosis. Firstly, MIC, which has the ability to quantify the degree of relevance in a data set, is applied to examine all potentially interesting relationships between sensors. Subsequently, sensors with high correlation are divided into several groups by the grouping thresholds. Two virtual sensors, which are constructed in each group by LSTM with different input sensors and corresponding to the same physical sensor, could have the ability to predict the value of physical sensors. High correlation sensors in each group improve the fitting effect of virtual sensors. Finally, sensor faults can be diagnosed by the absolute deviation which is generated by comparing the virtual sensors' output with the actual value measured from the air-cooled chiller. The performance of the proposed method is evaluated by using a real data set. Experimental results indicate that virtual sensors can be well constructed and the proposed method achieves a significant performance along with a low false alarm rate.

16.
ACS Appl Mater Interfaces ; 11(29): 26194-26203, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31283167

RESUMO

Fluorination of conjugated molecules has been established as an effective structural modification strategy to influence properties and has attracted extensive attention in organic solar cells (OSCs). Here, we have investigated optoelectronic and photovoltaic property changes of OSCs made of polymer donors with the non-fullerene acceptors (NFAs) ITIC and IEICO and their fluorinated counterparts IT-4F and IEICO-4F. Device studies show that fluorinated NFAs lead to reduced Voc but increased Jsc and fill-factor (FF), and therefore, the ultimate influence to efficiency depends on the compensation of Voc loss and gains of Jsc and FF. Fluorination lowers energy levels of NFAs, reduces their electronic band gaps, and red-shifts the absorption spectra. The impact of fluorination on the molecular order depends on the specific NFA, and the conversion of ITIC to IT-4F reduces the structural order, which can be reversed after blending with the donor PBDB-T. Contrastingly, IEICO-4F presents stronger π-π stacking after fluorination from IEICO, and this is further strengthened after blending with the donor PTB7-Th. The photovoltaic blends universally present a donor-rich surface region which can promote charge transport and collection toward the anode in inverted OSCs. The fluorination of NFAs, however, reduces the fraction of donors in this donor-rich region, consequently encouraging the intermixing of donor/acceptor for efficient charge generation.

17.
Diabetes Care ; 42(8): 1539-1548, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31152120

RESUMO

OBJECTIVE: Uncertainty remains regarding the predictive value of various glycemic measures as they relate to the risk of diabetes and its complications. Using the cutoffs recommended by the American Diabetes Association's 2010 criteria, we determined the associations of fasting plasma glucose (FPG), 2-h postload glucose (2h-PG), and HbA1c with the outcomes. RESEARCH DESIGN AND METHODS: Baseline medical history, FPG, 2h-PG, and HbA1c were obtained from a population-based cohort of 193,846 adults aged ≥40 years in China during 2011-2012. A follow-up visit was conducted during 2014-2016 in order to assess incident diabetes, cardiovascular disease (CVD), cancer, and mortality. RESULTS: We documented 8,063 cases of diabetes, 3,014 CVD-related events, 1,624 cases of cancer, and 2,409 deaths during up to 5 years of follow-up. Multivariable-adjusted risk ratios (95% CIs) of diabetes associated with prediabetes based on FPG of 100-125 mg/dL, 2h-PG of 140-199 mg/dL, or HbA1c of 5.7-6.4% (39-47 mmol/mol) were 1.60 (1.43-1.79), 2.72 (2.43-3.04), and 1.49 (1.36-1.62), respectively. Restricted cubic spline analyses suggested J-shaped associations of FPG, 2h-PG, and HbA1c levels with CVD, cancer, and mortality. Multivariable-adjusted hazard ratios (95% CIs) associated with untreated diabetes based on FPG ≥126 mg/dL, 2h-PG ≥200 mg/dL, or HbA1c ≥6.5% (48 mmol/mol) were 1.18 (1.05-1.33), 1.31 (1.18-1.45), and 1.20 (1.07-1.34) for CVD; 1.10 (0.92-1.32), 1.44 (1.25-1.67), and 1.08 (0.92-1.28) for cancer; and 1.37 (1.20-1.57), 1.57 (1.41-1.76), and 1.33 (1.17-1.52) for mortality, respectively. 2h-PG remained significantly associated with outcomes in models including FPG and HbA1c as spline terms. Furthermore, 2h-PG significantly improved the ability of the C statistic to predict diabetes, CVD, and mortality. CONCLUSIONS: 2h-PG remains independently predictive of outcomes in models including FPG and HbA1c. Therefore, in addition to FPG and HbA1c, routine testing of 2h-PG should be considered in order to better assess the risks of outcomes.

18.
Environ Pollut ; 252(Pt A): 897-906, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31212251

RESUMO

Atmospheric aerosols have been found to influence the development of planetary boundary layer (PBL) and hence to aggravate haze pollution in megacities. PBL height (PBLH) determines the vertical extent to which the most pollutant effectively disperses and is a key argument in pollution study. In this study, we quantitatively evaluate aerosol radiation effect on PBL, as well as assessment of surface cooling effect and atmosphere heating effect. All the data are measured at a site of Beijing from 2014 to 2017, of which PBLH is retrieved from micro pulse lidar and aerosol optical depth (AOD) from sunphotometer. Case study shows qualitatively that relative high aerosol load reduces PBLH, and in turn causes a high surface PM2.5 concentration. We preliminarily reveal the influential mechanism of aerosol on PBL. The influence of aerosol on the radiation flux of PBL is analyzed, with the correlation coefficient (R) of 0.938 between AOD and radiative forcing of BOA (RFBOA) and R = 0.43 between RFBOA and PBLH. Also, AOD is found to negatively correlate with PBLH (R = -0.41). With the increase of AOD, the cooling effect of surface is enhanced, and further impede the development of PBL. Due to aerosol-induced reduction of PBLH, near surface PM2.5 concentration surges and presents an exponential growth following AOD. Then, it is speculated and testified that the relationship between SSA (single scatting albedo) and PBLH would be determined by the location of absorbing aerosol within PBL. The upper PBL absorbing aerosol may decrease PBLH, while the lower absorbing aerosol appear to enhance PBLH. The study probably can provide effective observational evidence for understanding the effect of aerosol on PBL and be a reference of air pollution mitigation in Beijing and its surrounding areas.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Smog/análise , Atmosfera/química , Pequim
20.
J Nutr ; 149(8): 1443-1450, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31100111

RESUMO

BACKGROUND: Previous studies have found that meat-derived mutagens increase, and vitamin C or E decrease, the risk of pancreatic cancer. OBJECTIVE: The aim of this study was to determine whether intake of vitamin C or E modulates the association between meat-derived mutagen exposure and risk of pancreatic cancer. DESIGN: We conducted a case-control study in 1321 patients with pathologically confirmed pancreatic ductal adenocarcinoma (PDAC) and 1061 healthy controls (aged 28-88 y). Cases and controls were frequency-matched by age, sex, and race/ethnicity. Mutagen intake was assessed using a meat preparation questionnaire. Intakes of vitamin C, E, and other dietary components were assessed via a food-frequency questionnaire in a subset of 811 cases and 818 controls. ORs and 95% CIs were estimated in multivariable-adjusted logistic regression models. RESULTS: The risk of PDAC was not associated with meat intake but was associated with consumption of well-done grilled or barbecued chicken (OR: 1.57; 95% CI: 1.18, 2.09; P = 0.001). Intake of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline was associated with increased PDAC risk (Ptrend = 0.047). Participants in the highest, as compared with the lowest, quintile of 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (PhIP) intake experienced a 38% increased risk of PDAC (95% CI: 1.00, 1.90; P = 0.048). Intakes of total vitamin C or E from food and supplements or from supplements alone were each inversely associated with PDAC risk. Stratified analyses showed differential associations for PhIP intake and PDAC risk, such that risk increased among individuals with lower intake of vitamin C or E and decreased among those with higher vitamin intake. Significant interactions of dietary vitamin C, dietary vitamin E, and total vitamin E with PhIP intake were detected (Pinteraction = 0.023, <0.001, and 0.013, respectively). CONCLUSIONS: Consistent with experimental evidence, this study of 811 cases and 818 controls has shown that high intake of dietary vitamin C or E mitigates the risk of PhIP-related PDAC.

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