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1.
Dev Sci ; 23(1): e12856, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31081980

RESUMO

Diminished social motivation is hypothesized to explain abnormal face scanning pattern in individuals with autism spectrum disorder (ASD), especially reduced eye-looking time in ASDs than typically developing (TD) people. Here, we tested an alternative explanation that children with ASD may use a compensatory strategy to avoid direct eye contact by processing the eyes through peripheral vision. We compared the face scanning patterns of children with and without ASD in two conditions: in the clear condition, the face was completely visible; in the blur condition, by using the gaze-contingent paradigm, the whole face was blurred except for a small region being fixated at, thus children could not rely on the peripheral information to process the eyes. We found that children with ASD fixated less on the eyes than TD children in both conditions. Temporal-course analyses further revealed the possible motivation-based guidance of attention to process the eyes in the TD group but not in the ASD group. Additionally, we found that children with ASD scanned faces more randomly and less strategically than TD children. These results have ruled out the alternative hypothesis that the abnormal face scanning pattern in ASDs was due to their compensatory strategy to process eyes through peripheral vision, furthering our understanding of the mechanisms underlying their abnormal face scanning.

2.
Brain Stimul ; 13(1): 109-116, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31606448

RESUMO

BACKGROUND: Transcranial direct current stimulation (tDCS) has been explored in epilepsy with limited samples, varied parameters, and inconclusive results. We aimed to study the efficacy of tDCS for patients with refractory focal epilepsy. METHOD: We conducted a randomized, double-blind, sham-controlled, and three-arm (Group 1 (sham), Group 2 (20-min), and Group 3 (2 × 20-min)) tDCS parallel multicenter study. The primary outcome measurement was seizure frequencies (SFs). The study consisted of 28-days baseline, 14-days treatment, and 56-days follow-up. The cathode was placed over the epileptogenic focus, and the current intensity was 2 mA. The generalized estimating equations model, one-way analysis of variance, chi-square and Kruskal-Wallis test were used for analysis. RESULTS: Of the 82 enrolled patients, 70 patients were included for final analysis (Group 1, n = 21; Group 2, n = 24; and Group 3, n = 25). There was a significant reduction in SFs for both active tDCS groups compared with the sham group. Patients in Group 2 showed a significantly 50.73-21.91% greater reduction in SFs that lasted for 4 weeks (p = 0.008-0.060). Patients in Group 3 showed a significantly 63.19-49.79% greater reduction in SFs compared with the sham group that lasted for 5 weeks (p = 0.011-0.045). Patients in Group 3 had a 64.98-66.32% greater reduction in SFs at W9-W10, when compared with Group 2 (p = 0.021-0.022). CONCLUSION: Fourteen consecutive days tDCS significantly decreased SFs in patients with refractory focal epilepsy, with 2 × 20-min daily stimulation protocol being superior to 20-min daily stimulation protocol.

3.
J Affect Disord ; 260: 84-90, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31493644

RESUMO

BACKGROUND: Previous studies have investigated the role of cognitive factors in the relationship between stressful life events and depression; however, few studies comprehensively considered cognitive and personality factors. Therefore, this study investigated the multiple mediating roles of fatalism and core self-evaluations in the relationship between stressful life events and depression. METHODS: A cross-sectional survey was conducted with 537 Chinese university students (Mage = 20.20, SD = 1.38) at two universities in Guizhou and Sichuan provinces. The independent variable was stressful life events; mediating variables were fatalism and core self-evaluations; and the dependent variable was extent of depression. Multiple mediation analysis was performed using the PROCESS macro in SPSS. RESULTS: Significant positive correlations were found among stressful life events, fatalism, and depression, while core self-evaluations were significantly negatively correlated with stressful life events, fatalism, and depression. After adjusting for demographic variables, stressful life events directly and positively influenced depression (ß = 0.370, 95% CI = 0.292-0.448). Fatalism and core self-evaluations played multiple mediating roles in the relationship between stressful life events and depression, with stressful life events influencing depression through three mediation pathways (total mediation effect = 0.199, 95% CI = 0.145-0.254), which accounted for 53.85% of the total effect. LIMITATIONS: The data used in this study were self-reported by university students and measureed via cross-sectional designs. CONCLUSIONS: Stressful life events can influence depression either directly or indirectly by simultaneously increasing fatalism and lowering core self-evaluations (parallel mediation) or decreasing core self-evaluations through increasing the level of fatalism (serial mediation).

4.
ACS Nano ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31794189

RESUMO

Silver nanoparticles (AgNPs) are largely discharged into sewers and mostly accumulate in the sediments and sludge. The toxicity of silver nanoparticles to environmental microorganisms has attracted great attention. However, the effect of AgNPs on anaerobic ammonium-oxidizing (anammox) granules remains unknown. Here we present the underlying promotion mechanism of AgNPs on anammox granules from a morphological and molecular biology perspective. Our results demonstrate a positive effect of AgNPs on the proliferation of anammox bacteria. AgNPs resulted in a change in the three-dimensional structure of anammox granules and led to larger pore size and higher porosity. In addition, the diffusion capacity of the substrate and metal ions was enhanced. In addition, the expression of anammox-related enzymes, such as nitrite oxidoreductase (NirS), hydrazine dehydrogenase (Hdh), and hydrazine synthase (HZS) was upregulated. Therefore, the growth rate and the nitrogen removal performance of the anammox granules were improved. Our findings clarify the underlying mechanism of AgNPs on anammox granules and provide a promising method for the treatment of AgNPs-rich wastewater.

5.
Games Health J ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31800322

RESUMO

Balance is critical for older adults to perform daily activities. However, age-related declines in balance increase the risk of falls and severe injuries, such as bone fractures and head injuries. Exergames have been widely applied to improve health-related outcomes in older adults. This meta-analysis aims to quantify the effects of exergaming interventions on balance performance in healthy older adults. A literature search was performed using PubMed, ScienceDirect, SPORTDiscus, COCHRANE, EBSCO, and EMBASE. A total of 16 experimental studies met inclusion criteria for a full-text review. Data synthesis examined balance functions, including static, dynamic, proactive, and perceived balance abilities when performing daily activities. Intervention protocols of the reviewed studies included an average of two to three 40-minute exergaming sessions per week for 8 weeks. A random effects model identified significant effects in favor of the exergaming group, with moderate effect size in dynamic balance (Hedges' g = 0.36, 95% CI = 0.26-1.30, P < 0.001), and perceived balance (Hedges' g = 0.31, 95% CI = 0.04-0.58, P = 0.02); and considerable effect size in Chair Stand Test (Hedges' g = 0.78, 95% CI = 0.26-1.30, P = 0.003), and balance test batteries (Hedges' g = 0.72, 95% CI = 0.42-1.02, P < 0.001). No significant effect was found in the static balance (Hedges' g = 0.22, 95% CI = -0.31 to 0.76, P = 0.42), or proactive balance (Hedges' g = 0.54, 95% CI = -0.12 to 1.20, P = 0.11). Meta-analysis identified exergaming-associated benefits in older adults' balance function and confidence. This finding supports the feasibility of exergaming as a supplementary approach to improve balance for healthy older adults. Health professionals may optimize treatment effect by integrating exergaming sessions into a traditional balance exercise program.

6.
J Vis Exp ; (153)2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31789319

RESUMO

Elevated intraocular pressure (IOP) is a well-documented risk factor for glaucoma. Here we describe a novel, effective method for consistently inducing stable IOP elevation in mice that mimics the post-operative complication of using silicone oil (SO) as a tamponade agent in human vitreoretinal surgery. In this protocol, SO is injected into the anterior chamber of the mouse eye to block the pupil and prevent inflow of aqueous humor. The posterior chamber accumulates aqueous humor and this in turn increases the IOP of the posterior segment. A single SO injection produces reliable, sufficient, and stable IOP elevation, which induces significant glaucomatous neurodegeneration. This model is a true replicate of secondary glaucoma in the eye clinic. To further mimic the clinical setting, SO can be removed from the anterior chamber to reopen the drainage pathway and allow inflow of aqueous humor, which is drained through the trabecular meshwork (TM) at the angle of the anterior chamber. Because IOP quickly returns to normal, the model can be used to test the effect of lowering IOP on glaucomatous retinal ganglion cells. This method is straightforward, does not require special equipment or repeat procedures, closely simulates clinical situations, and may be applicable to diverse animal species. However, minor modifications may be required.

7.
Virol Sin ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792738

RESUMO

Viruses evolve rapidly and continuously threaten animal health and economy, posing a great demand for rapid and efficient genome editing technologies to study virulence mechanism and develop effective vaccine. We present a highly efficient viral genome manipulation method using CRISPR-guided cytidine deaminase. We cloned pseudorabies virus genome into bacterial artificial chromosome, and used CRISPR-guided cytidine deaminase to directly convert cytidine (C) to uridine (U) to induce premature stop mutagenesis in viral genes. The editing efficiencies were 100%. Comprehensive bioinformatic analysis revealed that a large number of editable sites exist in pseudorabies virus (PRV) genomes. Notably, in our study viral genome exists as a plasmid in E. coli, suggesting that this method is virus species-independent. This application of base-editing provided an alternative approach to generate mutant virus and might accelerate study on virulence and vaccine development.

8.
J Acad Nutr Diet ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31753772

RESUMO

BACKGROUND: Kuwaiti adults have experienced a rapid increase in cardiovascular disease (CVD) and its risk factors. Dietary patterns in the Kuwaiti diet associated with the increasingly higher CVD burden have not been adequately evaluated. OBJECTIVE: The objective of this study was to identify the major dietary patterns in Kuwaiti adults and examine their associations with CVD risk factors. DESIGN: This cross-sectional study examined data from the 2008-2009 National Nutrition Survey of the State of Kuwait. PARTICIPANTS/SETTING: The study included 555 Kuwaiti adults aged ≥20 years who completed a 24-hour dietary recall. MAIN OUTCOME MEASURES: The outcome measures included CVD risk factors such as obesity (body mass index), abdominal obesity (waist circumference), elevated blood pressure, dyslipidemia (blood lipid levels), diabetes (glucose and glycated hemoglobin levels), and metabolic syndrome. STATISTICAL ANALYSIS: Dietary patterns were identified using principal component analysis. The associations between dietary patterns and CVD risk factors were analyzed using survey-weighted multivariable linear and logistic regression models. RESULTS: Three dietary patterns were identified: vegetable-rich, fast food, and refined grains/poultry. Younger adults had higher adherence to the fast-food or refined-grains/poultry dietary patterns, whereas older adults had higher adherence to the vegetable-rich dietary pattern. The fast-food dietary pattern was positively associated with body mass index (ß=.94, 95% CI 0.08 to 1.79), waist circumference (ß=2.05, 95% CI 0.20 to 3.90 cm), and diastolic blood pressure (ß=1.62, 95% CI 0.47 to 2.77 mm Hg). The refined grains/poultry dietary pattern was positively associated with plasma glucose levels (ß=1.02, 95% CI 1.002 to 1.04 mg/dL [0.056 to 0.058 mmol/L]). Individuals in the highest tertile of the fast-food or refined-grains/poultry dietary patterns had higher odds of metabolic syndrome than those in the lowest tertile. CONCLUSIONS: The fast-food and refined grains/poultry dietary patterns were associated with high prevalence of CVD risk factors among Kuwaiti adults. The current findings underscore the need for prospective studies to further explore dietary pattern and CVD risk factor relationships among at-risk Kuwait adults.

9.
Nutrients ; 11(11)2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31684118

RESUMO

Patients with pediatric acute lymphoblastic leukemia (ALL) experience rapid weight gain during treatment and increases in weight are maintained throughout treatment and beyond. Without prompt interventions, altered dietary and physical activity behaviors may become difficult to reverse, contributing to obesity risk long-term. Fifteen children, aged 3-9 years, diagnosed with pediatric ALL who were on maintenance therapy or within two years of treatment completion (mean BMI percentile: 70.4th) and one parent from each family, were enrolled into a 12-week lifestyle intervention delivered remotely through web-based sessions and phone calls with a lifestyle coach. Outcomes were assessed at baseline and end of the intervention. Thirteen of the 15 enrolled families (86.7%) completed the intervention. Parents reduced the "pressure to eat" feeding practice (change in mean score: -0.60, 95% CI: -1.12 to -0.07; p-value = 0.03) post intervention. Children increased the consumption of milk (0.54 serving/d, 0.02 to 1.07; p-value = 0.04) and percent of calories from protein (2.54%, 0.22 to 4.87%; p-value = 0.04) and reduced the consumption of potatoes (-0.16 serving/d, -0.30 to -0.03; p-value = 0.02). No significant changes were observed for children's levels of physical activity, BMI, or waist circumference. Results from this pilot support the feasibility and preliminary efficacy of early lifestyle intervention among pediatric ALL survivors.

10.
J Surg Res ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31668429

RESUMO

BACKGROUND: "Choke vessels" are communicating conduits between adjacent perforasomes in the skin. Most researches focus mainly on the arterial aspect of the "choke vessels" and neglect the venous aspect, an imbalance needed to be addressed. MATERIALS AND METHODS: The study was divided into parts I, II, and III. Part I was for observation of the vascular morphological evolution in the choke zone after flap harvest in rats. Part II was for determination of the importance of the dilation of the arterial and venous components of "choke vessels" by preserving the iliolumbar artery (ILA group) or vein (ILV group). A laser Doppler flowmeter and a speckle flow imaging system were adopted for monitoring the hemodynamic impact caused by the different manipulation. Part III was for corroboration of part II by manipulation of other vessels. RESULTS: In part I, the arteries and veins between the iliolumbar and intercostal perforasomes underwent modest dilation, whereas the venules between the veins nearly quadrupled in diameter. In part II, flaps in the ILA group were much more intensive in blood perfusion than flaps in the ILV group. The flap necrosis rate was 0.31 ± 0.07 in the ILV group, being significantly larger than 0.10 ± 0.03 in the ILA group. Part III confirmed that venous superdrainage is less efficacious in reducing flap necrosis than arterial supercharging, in which the position of the additional artery was far more important than the diameter. CONCLUSIONS: The extensive dilation of the venous component of choke vessels makes a more potent compensatory role for venous drainage after flap harvest, indicating arterial supercharging is better in augmenting flap viability than venous superdrainage.

11.
Medicine (Baltimore) ; 98(47): e18019, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31764817

RESUMO

We aimed to investigate the correlation of homocysteine (Hcy) level with clinical characteristics, and explore its predictive value for major adverse cardiovascular events (MACE) risk in female patients with premature acute coronary syndrome (ACS).The serum Hcy level was detected from 1299 female patients with premature ACS. According to the tertile of Hcy level, patients were divided into 3 groups: lowest tertile group (≤9.1 µmol/L), middle tertile group (9.2-11.6 µmol/L) and highest tertile group (>11.6 µmol/L). MACE incidence was recorded and MACE-free survival was caculated with the median follow-up duration of 28.3 months.Increased Hcy correlated with older age (P < .001), higher creatinine level (P < .001), and enhanced uric acid level (P = .001), while reduced fasting glucose concentration (P < .001). MACE incidence was 10.7% and it was highest in highest tertile group (22.1%), followed by middle tertile group (7.7%) and lowest tertile group (2.4%) (P < .001). Receiver operating characteristic curve showed that Hcy distinguished MACE patients from non-MACE patients with the area under the curve of 0.789 (95% CI: 0.742-0.835). Kaplan-Meier curves revealed that MACE-free survival was shortest in Hcy highest tertile group, followed by middle tertile group and lowest tertile group (P < .001). Multivariate Cox analyses further showed that higher Hcy level was an independent predictive factor for poor MACE-free survival (middle tertile vs lowest tertile (P = .001, HR: 3.615, 95% CI: 1.661-7.864); highest tertile vs lowest tertile (P < .001, HR: 11.023, 95% CI: 5.356-22.684)).Hcy serves as a potential predictive factor for increased MACE risk in female patients with premature ACS.


Assuntos
Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/complicações , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Homocisteína/sangue , Fatores Etários , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de Risco
12.
Int J Cancer ; 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31709531

RESUMO

Increasing evidence suggests that IL-33 plays an important role in regulating tumor development. However, conflicting results, obtained from numerous studies, have highlighted the divergent functions of IL-33. The detailed mechanisms by which IL-33 modulates tumor development merit further investigation. Here, we report that IL-33 administration can effectively inhibit the development of pulmonary metastasis of breast cancer in a mouse. In our model, IL-33 promotes the production of TNF-α by macrophages, which increases IL-33 specific receptor (ST2) expression on natural killer (NK) cells and is pivotal in IL-33-induced NK cell activation. IL-33 treatment also facilitates the production of CCL5 in the lung by eosinophils and CD8+ T cells, which mediates the recruitment of NK cells to the tumor microenvironment. The systemic activation and local recruitment of NK cells result in potent tumor rejection in the lung. Our study reports a novel mechanism for the IL-33-meditated suppression of metastatic cancer and provides potential therapeutic strategies for targeting metastatic tumor.

13.
Stem Cell Res Ther ; 10(1): 324, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730021

RESUMO

BACKGROUND: As the precursors of sperm and eggs, human primordial germ cells (hPGCs) emerge as early as weeks 2 to 3 of post-implantation development. Recently, robust hPGC induction models have been established in vitro with different protocols, but global 5mC/5hmC epigenetic reprogramming is not initiated in vitro. Previous studies found that vitamin C can enhance Tet (ten-eleven translocation) enzyme expression and improve 5hmC level in cells. But the effect of vitamin C supplementation on hPGC in vitro induction is still unknown. METHODS: We generated a gene-edited human embryonic stem cell (hESC) line carrying a BLIMP1-mkate2 reporter by CRISPR/Cas9 technology and used flow cytometry to optimize the PGC differentiation protocol; meanwhile, the expression of PGC genes (BLIMP1, TFAP2C, SOX17, OCT4) was evaluated by qRT-PCR. When different concentrations of vitamin C were added to the induction medium, the percentage of hPGCLCs (hPGC-like cells) was analyzed by flow cytometry; dot blot and ELISA were used to detect the levels of 5hmC and 5mC. The expression of TET enzymes was also evaluated by qRT-PCR. RESULTS: We optimized the PGC differentiation protocol with the BLIMP1-mkate reporter hESCs, and the efficiency of PGC induction in vitro can be improved to 30~40%. When 50 µg/mL vitamin C was added, the derived hPGCLCs not only upregulated the expression of key genes involved in human early germ cell development such as NANOS3, TFAP2C, BLIMP1, and SOX17, but also increased the levels of 5hmC and TET enzymes. CONCLUSIONS: Taken together, supplementation of vitamin C can promote the in vitro induction of hPGCLCs from hESCs, which might be related to vitamin C-mediated epigenetic regulations during the differentiation process.

14.
J Neurosurg ; : 1-9, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783364

RESUMO

OBJECTIVE: The current standard initial therapy for pilocytic astrocytoma is maximal safe resection. Radiation therapy is considered for residual, recurrent, or unresectable pilocytic astrocytomas. However, the optimal radiation strategy has not yet been established. Here, the authors describe the outcomes of stereotactic radiosurgery (SRS) for pilocytic astrocytoma in a large multiinstitutional cohort. METHODS: An institutional review board-approved multiinstitutional database of patients treated with Gamma Knife radiosurgery (GKRS) between 1990 and 2016 was queried. Data were gathered from 9 participating International Radiosurgery Research Foundation (IRRF) centers. Patients with a histological diagnosis of pilocytic astrocytoma treated using a single session of GKRS and with at least 6 months of follow-up were included in the analysis. RESULTS: A total of 141 patients were analyzed in the study. The median patient age was 14 years (range 2-84 years) at the time of GKRS. The median follow-up was 67.3 months. Thirty-nine percent of patients underwent SRS as the initial therapy, whereas 61% underwent SRS as salvage treatment. The median tumor volume was 3.45 cm3. The tumor location was the brainstem in 30% of cases, with a nonbrainstem location in the remainder. Five- and 10-year overall survival rates at the last follow-up were 95.7% and 92.5%, respectively. Five- and 10-year progression-free survival (PFS) rates were 74.0% and 69.7%, respectively. On univariate analysis, an age < 18 years, tumor volumes < 4.5 cm3, and no prior radiotherapy or chemotherapy were identified as positive prognostic factors for improved PFS. On multivariate analysis, only prior radiotherapy was significant for worse PFS. CONCLUSIONS: This represents the largest study of single-session GKRS for pilocytic astrocytoma to date. Favorable long-term PFS and overall survival were observed with GKRS. Further prospective studies should be performed to evaluate appropriate radiosurgery dosing, timing, and sequencing of treatment along with their impact on toxicity and the quality of life of patients with pilocytic astrocytoma.

15.
Phys Med Biol ; 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783390

RESUMO

OBJECTIVE: To achieve accurate and fast deformable image registration (DIR) for pulmonary CT, we proposed a Multi-scale DIR framework with unsupervised Joint training of Convolutional Neural Network (MJ-CNN). METHODS: MJ-CNN contains three models at multi-scale levels for a coarse-to-fine DIR to avoid being trapped in a local minimum. It is trained based on image similarity and deformation vector field (DVF) smoothness, requiring no supervision of ground-truth DVF. The three models are first trained sequentially and separately for their own registration tasks, and then are trained jointly for an end-to-end optimization under the multi-scale framework. In this study, MJ-CNN was trained using public SPARE 4D-CT data. The trained MJ-CNN was then evaluated on public DIR-LAB 4D-CT dataset as well as clinical CT-to-CBCT and CBCT-to-CBCT registration. RESULTS: For 4D-CT inter-phase registration, MJ-CNN achieved comparable accuracy to conventional iteration optimization-based methods, and showed the smallest registration errors compared to recently published deep learning-based DIR methods, demonstrating the efficacy of the proposed multi-scale joint training scheme. Besides, MJ-CNN trained using one dataset (SPARE) could generalize to a different dataset (DIR-LAB) acquired by different scanners and imaging protocols. Furthermore, MJ-CNN trained on 4D-CTs also performed well on CT-to-CBCT and CBCT-to-CBCT registration without any re-training or fine-tuning, demonstrating MJ-CNN's robustness against applications and imaging techniques. MJ-CNN took about 1.4 seconds for DVF estimation and required no manual-tuning of parameters during the evaluation. CONCLUSION: MJ-CNN is able to perform accurate DIR for pulmonary CT with nearly real-time speed, making it very applicable for clinical tasks.

16.
Clin Exp Allergy ; 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31782836

RESUMO

BACKGROUND: Previous studies have suggested an association between season of birth and risk of childhood asthma and allergic disease. The association may be modified by birth year and region, or mediated by respiratory tract infections. OBJECTIVE: We aimed to estimate the association between season of birth and risk of childhood asthma/wheeze or allergic rhinoconjunctivitis in a population-based setting, and the mediating effect of lower respiratory infections. METHODS: Two population-based cohorts were identified from the nationwide Swedish Medical Birth, Patient and Prescribed Drug Registers. The association between birth month/season and asthma/wheeze incidence was analysed using Cox proportional regression in the younger cohort born 2005-2010 (n=582,494) and asthma/allergic rhinoconjunctivitis prevalence during the 7th year of life using log-binomial models in the older cohort born 2001-2004 (n=367,583). Interactions were formally tested. Mediation analyses to address the effect of lower respiratory infections were performed in the older cohort using the R package 'medflex'. RESULTS: Children born during fall and winter had an increased risk of asthma/wheeze after 2 years of age in the younger cohort; hazard ratio 1.24 (95% confidence interval, CI 1.17, 1.33) for winter and risk of prevalent asthma during their 7th year of life in the older cohort; prevalence ratio (PR) 1.12 (95% CI 1.08, 1.16) for winter. These estimates were partly mediated by lower respiratory infections; the indirect effect for winter compared to summer was PR 1.03 (95% CI 1.03, 1.04). The association was similar for allergic rhinoconjunctivitis in the 7th year of life, but not mediated by respiratory infections. CONCLUSION: We found that the association between season of birth and risk of childhood asthma/wheeze, but not allergic rhinoconjunctivitis, is partly mediated through lower respiratory infections. CLINICAL RELEVANCE: This has important implications for patient care, such as asthma management programs to notify timing of seasonality for viral respiratory tract infections.

17.
Elife ; 82019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31711568

RESUMO

While the rare occurrence of child loss is accompanied by reduced life expectancy of parents in contemporary affluent populations, its impact in developing societies with high child mortality rates is unclear. We identified all parents in Iceland born 1800-1996 and compared the mortality rates of 47,711 parents who lost a child to those of their siblings (N = 126,342) who did not. The proportion of parents who experienced child loss decreased from 61.1% of those born 1800-1880 to 5.2% of those born after 1930. Child loss was consistently associated with increased rate of maternal, but not paternal, death before the age of 50 across all parent birth cohorts; the relative increase in maternal mortality rate ranged from 35% among mothers born 1800-1930 to 64% among mothers born after 1930. The loss of a child poses a threat to the survival of young mothers, even during periods of high infant mortality rates.

18.
Heart ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727634

RESUMO

OBJECTIVE: To investigate if marital status is associated with risk of cardiovascular disease (CVD) and to explore the potential influence of leucocyte telomere length (LTL), a marker of biological ageing, on such association. DESIGN: Population-based prospective cohort study SETTINGS: Swedish Twin Registry. PARTICIPANTS: Based on the Screening Across the Lifespan Twin Study from the Swedish Twin Registry, we included 10 058 twins born between 1900 and 1958 who underwent an interview between 1998 and 2002 during which information about marital status was collected. Blood samples from these participants were subsequently collected between 2004 and 2008 and used for LTL assessment using quantitative PCR technique. MAIN OUTCOME MEASURES: Incident cases of CVD were identified through the Swedish Patient Register and Causes of Death Register through December 31, 2016. Multivariable linear regression and Cox proportional hazards regression models were used to estimate the regression coefficients (ßs) and HRs with 95% CIs respectively. Potential confounders included age, sex, educational attainment and body mass index. RESULTS: A total of 2010 participants were diagnosed with CVD during a median follow-up of 9.8 years. LTL was shorter among individuals living singly, including those who were divorced or separated (ß:-0.014, 95% CI: -0.035, 0.007), widowed (ß:-0.035, 95% CI: -0.061, -0.010), or living alone (ß:-0.033, 95% CI: -0.052, -0.014), than individuals who were married or cohabitating. One SD increase of LTL was associated with a lower risk of CVD (HR: 0.79, 95% CI: 0.66, 0.93). Individuals who were divorced or separated, widowed, or living alone had a higher risk of CVD than individuals who were married or cohabitating. The summary HR of CVD was 1.21 (95% CI: 1.08, 1.35) when comparing individuals who were living singly, regardless of reason, with the individuals who were married or cohabitating. LTL appeared to mediate little of the association between marital status and CVD (HR additionally adjusted for LTL: 1.20; 95% CI: 1.08, 1.34). CONCLUSIONS: Living singly, regardless of reason, was associated with a shorter LTL and a higher risk of CVD. The association between marital status and CVD was however not greatly attributable to telomere shortening.

19.
J Appl Clin Med Phys ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729812

RESUMO

PURPOSE: This technical note aims to investigate the dosimetric impact of stray radiation on the Common Control Unit (CCU) of the IBA Blue Phantom2 and the measured beam data. METHODS: Three CCUs of the same model were used for the study. The primary test CCU was placed at five distances from the radiation beam central axis. At each distance, a set of depth dose and beam profiles for two open and two wedge fields were measured. The field sizes were 10 × 10 cm2 and 30 × 30 cm2 for the open fields, and 30 × 30 cm2 and 15 × 15 cm2 for the 30° and 60° wedges, respectively. The other two CCUs were used to cross check the data of the primary CCU. Assuming the effect of stray radiation on the data measured at the farthest reachable distance 4.5 m is negligible, the dosimetric impact of stray radiation on the CCU and consequently on the measured data can be extracted for analysis by comparing it with those measured at shorter distances. RESULTS: The results of three CCUs were consistent. The dosimetric impact of stray radiation was greater for lower energies at larger field sizes. For open fields, the data variation was up to 4.5% for depth dose curves and 7.1% for beam profiles. For wedge fields, the data variation was up to 9.3% for depth dose curves and 10.6% for beam profiles. Moreover, for wedge field profiles in the wedge direction, they became flatter as the CCU was placed closer to the primary radiation beam, manifesting smaller wedge angles. CONCLUSION: The stray radiation added a uniform background noise on all measured data. The magnitude of the noise is inversely proportional to the square of the distance of the CCU to the primary radiation beam, approximately following the inverse square law.

20.
Acc Chem Res ; 52(11): 3177-3187, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31697061

RESUMO

Climate change represents one of the most important environmental issues of our time. Due to high levels of anthropogenic CO2 emissions, atmospheric CO2 has for the first time ever exceeded 415 ppm and has increased from 315 ppm in 1950. An annual increase in atmospheric CO2 of ∼2 ppm is equal to a net increase of ∼15.6 billion tons of CO2. The combustion of fossil fuels for electricity and transportation is still the main reason accounting for the CO2 accumulation. On the top of that, fossil fuels are widely used in our modern industry for the productions of indispensable social staples. For instance, the millennia old thermal reduction of iron ore by charcoal or baked coal (3C + 2Fe2O3 → 4Fe + 3CO2) continues as the main method for the production of iron. The artificial fertilizer ammonia boosts the global population and is mainly produced from the Haber-Bosch process, in which hydrogen is generated via steam reforming of methane (CH4 + 2H2O → 4H2 + CO2). Sequestration and diminution of CO2 require the development of a portfolio of technologies on (1) efficient and long-term harvesting of renewable energy, that is, solar, not only for electricity but also directly as the energy force in vital chemical processes, wherever possible, (2) carbon-neutral processes to replace current industrial processes that emit vast amounts of CO2, such as iron and ammonia production, and (3) new, low-cost technologies for CO2 capture and conversion with particular interests in the exploration of CO2 as the feedstock for fuels or other valuable chemicals and materials. To this end, we conducted some studies on the sustainable synthesis of ammonia and iron with net-zero CO2 emissions and large-scale CO2 capture and conversion into fuels and high value nanocarbon products via electrolysis in molten salt(s) with the introduction of the Solar Thermal Electrochemical Process (STEP). In STEP, solar UV-visible energy is focused on a photovoltaic device that generates the electricity to drive the electrolysis, while concurrently the solar thermal energy is focused on a second system to generate heat for the electrolysis cell. The utilization of the full spectrum of sunlight in STEP results in a higher solar energy efficiency than other solar conversion processes. STEP has been applied to conduct (1) CO2-free ammonia synthesis from nitrogen and water with the aid of nano-Fe2O3 in a molten hydroxide electrolyte, (2) CO2-free production of iron via electrochemical reduction of iron ore in molten carbonate, (3) CO2 capture and conversion into nanostructured carbon products as well as fuels in molten or mixed molten electrolytes, and (4) organic electrosynthesis of benzoic acid from benzene without overoxidizing into CO2. In this Account, we highlight some recent achievements in these topics and propose that using STEP is a highly efficient strategy for saving energy and, consequently, the environment. STEP is an ideal tool that can theoretically be applied to all endothermic reactions.

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