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1.
Int J Hyperthermia ; 37(1): 1159-1173, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33003967

RESUMO

PURPOSE: To characterize temperature fields and tissue damage profiles of large-volume hyperthermia (HT) induced by magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU) in deep and superficial targets in vivo in a porcine model. METHODS: Nineteen HT sessions were performed in vivo with a commercial MRgHIFU system (Sonalleve® V2, Profound Medical Inc., Mississauga, ON, Canada) in hind leg muscles of eight pigs with temperature fields of cross-sectional diameter of 58-mm. Temperature statistics evaluated in the target region-of-interest (tROI) included accuracy, temporal variation, and uniformity. The impact of the number and location of imaging planes for feedback-based temperature control were investigated. Temperature fields were characterized by time-in-range (TIR, the duration each voxel stays within 40-45 °C) maps. Tissue damage was characterized by contrast-enhanced MRI, and macroscopic and histopathological analysis. The performance of the Sonalleve® system was benchmarked against a commercial phantom. RESULTS: Across all HT sessions, the mean difference between the average temperature (Tavg) and the desired temperature was -0.4 ± 0.5 °C; the standard deviation of temperature 1.2 ± 0.2 °C; the temporal variation of Tavg for 30-min HT was 0.6 ± 0.2 °C, and the temperature uniformity was 1.5 ± 0.2 °C. A difference of 2.2-cm (in pig) and 1.5-cm (in phantom) in TIR dimensions was observed when applying feedback-based plane(s) at different locations. Histopathology showed 62.5% of examined HT sessions presenting myofiber degeneration/necrosis within the target volume. CONCLUSION: Large-volume MRgHIFU-mediated HT was successfully implemented and characterized in a porcine model in deep and superficial targets in vivo with heating distributions modifiable by user-definable parameters.

2.
Sci Rep ; 10(1): 16435, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009459

RESUMO

PM2.5 pollution has become a serious urban environmental problem, especially in developing countries with increasing urbanization. Understanding the proportion of PM2.5 generation sources has laid a foundation for better PM2.5 concentration reduction This paper used Point of Interesting (POI)data, building profile data of Xi'an, PM2.5 concentration and wind monitoring data of five provinces near Xi'an as the basic data. And this paper studied the spatial distribution of various buildings in Xi'an, the temporal and spatial distribution of PM2.5 in Xi'an and the five provinces, and found that the spatial distribution of PM2.5 concentration in Xi'an and the building distribution in Xi'an does not match. Based on this, a quantitative model of PM2.5 concentration in Xi'an, energy consumption, wind, and other factors is established through the qualitative and quantitative analysis of PM2.5 concentration in Xi'an. Entropy theory and dissipative structure theory are applied to analyze this phenomenon. The results show PM2.5 in Xi'an mainly comes from the spread of PM2.5 in the five provinces. The PM2.5 generated by energy consumption in Xi'an is not enough to cause serious PM2.5 pollution. And further suggestions on how to reduce PM2.5 concentration in Xi'an are put forward.

3.
Aging Clin Exp Res ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33026595

RESUMO

BACKGROUND: It was reported that inhaled corticosteroids (ICS) treatment may affect local immunity and microbial community of the airway. However, whether ICS treatment increases the risk of influenza in patients with asthma remains unclear. This meta-analysis aimed to compare the risk of influenza between ICS and non-ICS treatment in patients with asthma. METHODS: PubMed, Embase, Cochrane Library and Clinical Trials.gov were searched from inception until November 2019. Randomized controlled trials (RCTs) were included that compared ICS treatment with non-ICS treatment on the risk of influenza in patients with asthma. Meta-analyses were conducted by the Peto approach and Mantel-Haenszel approach with corresponding 95% CIs. RESULTS: Nine trials involving 6486 patients were included in this meta-analysis. The risk of influenza was not different between ICS treatment and the control groups (Peto OR: 1.01, 95% CI 0.74-1.37, P = 0.95). The results of subgroup analyses based on durations (long-term and short-term treatment), doses (high-, medium- and low-dose treatment) and types (fluticasone and budesonide treatment) of ICS were consistent with the above pooled results. Moreover, subgroup analysis based on patients' age also revealed that use of ICS did not increase the risk of influenza. Results of the two meta-analysis approaches were similar. CONCLUSIONS: Use of ICS does not increase the risk of influenza in patients with asthma. This study adds to safety evidence of ICS as a regular controller treatment for patients with asthma.

4.
IEEE Trans Cybern ; PP2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33001820

RESUMO

This article presents a generalized collaborative representation-based classification (GCRC) framework, which includes many existing representation-based classification (RC) methods, such as collaborative RC (CRC) and sparse RC (SRC) as special cases. This article also advances the GCRC theory by exploring theoretical conditions on the general regularization matrix. A key drawback of CRC and SRC is that they fail to use the label information of training data and are essentially unsupervised in computing the representation vector. This largely compromises the discriminative ability of the learned representation vector and impedes the classification performance. Guided by the GCRC theory, we propose a novel RC method referred to as discriminative RC (DRC). The proposed DRC method has the following three desirable properties: 1) discriminability: DRC can leverage the label information of training data and is supervised in both representation and classification, thus improving the discriminative ability of the representation vector; 2) efficiency: it has a closed-form solution and is efficient in computing the representation vector and performing classification; and 3) theory: it also has theoretical guarantees for classification. Experimental results on benchmark databases demonstrate both the efficacy and efficiency of DRC for multiclass classification.

5.
Biol Trace Elem Res ; 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33015744

RESUMO

The article High-Dose Aluminum Exposure Further Alerts Immune Phenotype in Aplastic Anemia Patients, written by Yao Zuo, Xiang Lu, Xiaochao Wang, Suren R. Sooranna, Liju Tao, Shiqiang Chen, Hongwen Li, Dan Huang, Guanye Nai, Hong Chen, Chunfeng Pan, Caihong Huang and Yanmin Pang.

6.
J Cardiothorac Surg ; 15(1): 302, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028372

RESUMO

OBJECTIVES: This study aimed to identify the incidence rate of Acute kidney injury (AKI) in our center and predict in-hospital mortality and long-term survival after heart transplantation (HTx). METHODS: This single-center, retrospective study from October 2009 and March 2020 analyzed the pre-, intra-, and postoperative characteristics of 95 patients who underwent HTx. AKI was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Risk factors were analyzed by multivariable logistic regression models. The log-rank test was used to compare long-term survival. RESULTS: Thirty-three (34.7%) patients developed AKI. The mortality in hospital in HTx patients with and without AKI were 21.21 and 6.45%, respectively (P < 0.05). Recipients in AKI who required renal replacement therapy (RRT) had a hospital mortality rate of 43.75% compared to 6.45% in those without AKI or RRT (P < 0.0001). A long cardiopulmonary bypass (CPB) time (OR:11.393, 95% CI: 2.183 to 59.465, P = 0.0039) was positively related to the occurrence of AKI. A high intraoperative urine volume (OR: 0.031, 95% CI: 0.005 to 0.212, P = 0.0004) was negatively correlated with AKI. AKI requiring RRT (OR, 11.348; 95% CI, 2.418-53.267, P = 0.002) was a risk factor for mortality in hospital. Overall survival in patients without AKI at 1 and 3 years was not different from that in patients with AKI (P = 0.096). CONCLUSIONS: AKI is common after HTx. AKI requiring RRT could contribute powerful prognostic information to predict mortality in hospital. A long CPB time and low intraoperative urine volume are associated with the occurrence of AKI.

7.
Gene ; : 145201, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33035617

RESUMO

Single nucleotide polymorphism (SNP) has recently become one of the ideal genetic markers. SNP refers to the DNA sequence polymorphism caused by double nucleotide variation in the genome, including the conversion or transversion of segmented bases. The synthesis and metabolism of triglycerides are related to the changes of energy in the body of livestock, which in turn affects their growth and development. Studies have shown that MOGAT1 gene plays a role in the route of triglyceride synthesis. PCR-RFLP and agarose gel electrophoresis technology were used to type the SNP site of MOGAT1 gene at g.25940T>C in this study. Association analysis between typing results and growth trait data was detected by SPSS 20.0 software. Results show that MOGAT1 gene was in a low level of heterozygosity in Xianan, Qinchuan and Pinan cattle population(0

8.
Am J Gastroenterol ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33038129

RESUMO

INTRODUCTION: Environmental factors related to urbanization and industrialization are believed to be involved in inflammatory bowel disease (IBD) development, but no study has looked at the association between greenspace and IBD. METHODS: We conducted a retrospective cohort study using linked population-based health administrative and environmental data sets. The study population comprised 2,715,318 mother-infant pairs from hospital births in Ontario, Canada, between April 1, 1991, and March 31, 2014. We measured the exposure to residential greenspace using the normalized difference vegetation index derived using remote-sensing methods. Average greenspace was estimated for the pregnancy and childhood periods. We used mixed-effects Cox proportional hazard models to assess potential associations between residential greenspace and the risk of developing IBD before 18 years while adjusting for covariates including sex, maternal IBD, rural/urban residence at birth, and neighborhood income. RESULTS: There were 3,444 IBD diagnoses that occurred during follow-up. An increase in the interquartile range of residential greenspace during the childhood period was associated with a lower risk of developing pediatric-onset IBD (hazard ratio [HR] 0.77, 95% confidence interval [CI] 0.74-0.81). This relationship was significant for both ulcerative colitis (HR 0.72 95% CI 0.67-0.78) and Crohn's disease (HR 0.81, 95% CI 0.76-0.87). There was a linear dose response across increasing quartiles of greenspace (P < 0.0001). No consistent association was detected between maternal intrapartum greenspace exposure and pediatric-onset IBD. DISCUSSION: Higher exposure to residential greenspace during childhood was associated with a reduced risk of IBD, suggesting a novel avenue to prevent IBD in children.

9.
Zootaxa ; 4810(1): zootaxa.4810.1.4, 2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-33055911

RESUMO

Taiwan is one of the richest in the world in terms of eel fauna. In this study, we examined the osteological and morphological characteristics of eels in the family Muraenidae. Furthermore, we focused on the neurocranium of 34 muraenid species in the genera Echidna (2), Enchelycore (3), Gymnomuraena (1), Gymnothorax (25), Scuticaria (1), Strophidon (1), and Uropterygius (1), which are caught in Taiwanese waters. This paper shows the results of a comparative study on osteological characters of the neurocranium including the ratio of nine length characters and 20 diagnostic characters for 34 eel species in the family Muraenidae. The subfamily Uropterygiinae is distinguished from the subfamily Muraeninae in having the lowest value on the depth of mid pre-orbit due to the termination of the ethmoidal crest toward premaxilla. Moreover, aside from Gymnomuraena zebra, the species of subfamily Uropterygiinae have the lowest orbit length. These results in neurocranial comparative morphology between the species are consistent with their previous classification based on molecular results. These morphological and osteological characters may be valuable for taxonomic purposes and might be used as the basis for further studies on the status of genera in Muraenidae.

11.
J Geriatr Oncol ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33059998

RESUMO

BACKGROUND: Older people with lung cancer are often frail and unfit due to their cancer and co-morbidities and may tolerate cancer treatments poorly. Physical activity (PA) and a healthy diet offer quality of life benefit to people with cancer before, during, and post treatment. However, older adults are poorly represented in the clinical trials on which recommendations were made. OBJECTIVE: To assess the acceptability, usefulness, and practicality of delivering a tailored wellbeing (PA and nutrition) intervention for older adults with lung cancer before, during, and after cancer treatments (chemotherapy and/or immunotherapy). METHODS: Semi-structured interviews conducted with nine patients with lung cancer and three patients with mesothelioma, ≥70 years and ten informal carers, and nine Multidisciplinary Team (MDT) members. A topic guide covered the acceptability, usefulness, and practicality of a wellbeing intervention as well as specific feedback on individual components. Data were subjected to thematic analysis. FINDINGS: Four themes were generated: current lack of wellbeing care in clinical work; preferred "can have" dietary and "can do" PA advice; peer support as facilitating factor; and barriers to compliance including patients' psychological and physical issues as well as current cancer pathway and staffing issues. CONCLUSION: Older adults with lung cancer would welcome a proactive, clear and instructive, wellbeing intervention. Many barriers to compliance exist, particularly before and during cancer treatments due to the psycho-social impact of diagnosis, and the effects of cancer treatment. The intervention must be tailored to individual need and address physical limitations, psychological and social welfare in addition to PA and nutritional advice.

12.
Development ; 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060128

RESUMO

Lymphatic vasculature is an integral part of digestive, immune and circulatory systems. The homeobox transcription factor PROX1 is necessary for the development of lymphatic vessels, lymphatic valves (LVs) and lymphovenous valves (LVVs). We and others previously reported a feedback loop between PROX1 and Vascular Endothelial Growth Factor-C (VEGF-C) signaling. PROX1 promotes the expression of the VEGF-C receptor VEGFR3 in lymphatic endothelial cells (LECs). In turn, VEGF-C signaling maintains PROX1 expression in LECs. However, the mechanisms of PROX1/VEGF-C feedback loop remain poorly understood. Whether VEGF-C signaling is necessary for LV and LVV development is also unknown. Here, we report for the first time that VEGF-C signaling is necessary for valve morphogenesis. We have also discovered that the transcriptional co-activators YAP and TAZ are required to maintain PROX1 expression in LVs and LVVs in response to VEGF-C signaling. Deletion of Yap and Taz in the lymphatic vasculature of mouse embryos did not affect the formation of LVs or LVVs, but resulted in the degeneration of these structures. Our results have identified VEGF-C/YAP/TAZ as a critical molecular pathway in valve development.

13.
Gut Microbes ; 12(1): 1-12, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33031021

RESUMO

HELICOBACTER PYLORI: (H. pylori), a common pathogenic bacterium in the stomach, has been demonstrated to be a major cause of gastric cancer (GC). The typical pathological evolution of H. pylori infection-induced GC involves development from gastric atrophy, via intestinal metaplasia (IM) and dysplasia, to intestinal-type GC. During this process, IM is considered to be an "irreversible point" that significantly increases the risk for GC. Therefore, the elucidation of the mechanism underlying IM is of great significance for the prevention and treatment of gastric mucosal carcinogenesis associated with H. pylori infection. Caudal type homeoboxes (CDXs) are transcription factors involved in intestinal differentiation establishment and the maintenance of normal intestinal mucosa and IM. H. pylori infection increases the expression of CDXs through epigenetic regulation, the nuclear factor-kappaB signaling pathway and its downstream proinflammatory factors, and the transforming growth factor-beta signaling pathway, leading to the progression from normal gastric mucosa to IM. However, the precise mechanisms of gastric intestinal metaplasia have not yet been fully elucidated. In this review, we focus on research progress revealing the functions of CDXs in H. pylori infection-induced IM, as well as the regulators modulating this process.

14.
Brain Pathol ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33032379

RESUMO

Pediatric low-grade gliomas were shown to be characterized by an array of distinct molecular aberrations. The recent cIMPACT-4 consensus proposed pediatric low-grade gliomas of the diffuse type to be characterized by distinct molecular changes rather than distinct histological features (2). Very recently, Fukuoka et al. described a small series of pediatric oligodendroglioma-like tumors with BRAF V600E mutations (3). Interestingly, they exhibited molecular changes usually associated with adult high grade gliomas: chromosome instability, chromosome 7 gains and chromosome 10 loss, but had an indolent natural history.

15.
Brain Imaging Behav ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033984

RESUMO

Numerous studies have shown that restrained eating is not an effective weight loss strategy. Restrained eaters often suppress their desires and thoughts about tasty food, which makes it more difficult to control themselves in subsequent eating behavior. The ego depletion impairs conflict monitoring abilities. Therefore, this study explored the effects of food thoughts suppression on restrained eaters' conflict monitoring. Therefore, this study used functional magnetic resonance imaging (fMRI) methods to explore changes in the activity of brain regions involved in conflict monitoring when restrained eaters choose between high- and low-calorie foods after either suppressing or not suppressing thoughts about food. The results showed that, compared to the control condition, after suppression of such thoughts, restrained eaters chose more high-calorie foods and displayed decreased activity in the dorsal anterior cingulate cortex-an important region in charge of conflict monitoring. At the same time, the functional coupling of the dorsal anterior cingulate cortex and the precuneus increased. Our findings suggest that restrained eaters' suppression of thoughts about tasty food could lead to a decline in their ability to monitor conflicts between current behaviors and goals, which in turn leads to unhealthy eating behavior.

16.
Dalton Trans ; 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33034331

RESUMO

Non-centrosymmetric metal chalcogenides such as AgGaS2 and AgGaSe2 are two of the commercial nonlinear optical (NLO) crystals widely used in the infrared (IR) region. Nevertheless, the inherent incompatibility between the wide energy gap (Eg) and large second-harmonic generation (SHG) efficiency (dij) hinders their high-power laser applications. Recently, the development of salt-inclusion chalcogenides with non-centrosymmetric structures has attracted more and more attention and interest owing to their intensive potential applications originating from their wide Eg, strong dij, ultrahigh laser-induced damage thresholds (LIDTs) and large IR transmission range. In this frontier paper, we review the recent progress of salt-inclusion chalcogenides (including 28 related compounds) as favourable candidates for IR-NLO materials, which can be divided into 3 types according to their chemical compositions and structural characteristics: (i) the [RaXb][GanQ2n] type and its derivatives, (ii) [NaBa4Cl][Ge3S10] and its derivatives, and (iii) the [A3X][MB12(MQ4)3] type. The relationships between the non-centrosymmetric structures and NLO properties of these 3 types of compounds are summarized and briefly remarked. In addition, the present challenges of creating new IR-NLO salt-inclusion chalcogenides and future perspectives in this field are discussed.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33029772

RESUMO

In order to effectively promoting green consumption, this paper constructs a theoretical model from the perspective of double-entry mental accounting to study the impact of perceived value and consumption sensitivity on green consumption intention. Conducting a large-scale empirical study, we analyzed the influence of perceived value on green consumption intention, tested the mediating effect of double-entry mental accounting, and explored the moderating effect of consumption sensitivity on perceived value and green consumption intention. The results indicate that perceived benefits are significantly positively correlated with green consumption intention, and perceived sacrifices are significantly negatively correlated with green consumption intention. In addition, perceived benefits have a greater impact on green consumption intention than perceived sacrifices. Double-entry mental accounting plays a significant mediating role on the path from perceived value to green consumption intention. Compared with the mediating effect of the coefficient of pleasure attenuation and the coefficient of pain buffering, the mediating effect of coefficient of pleasure attenuation is stronger and the mediating path is more important. This study concludes that individuals with lower consumption sensitivity are more willing to buy green products. When consumption sensitivity is lower, the negative correlation between perceived sacrifices and green consumption intention is stronger. Finally, corresponding policies are proposed based on the results of this study.

18.
Breast Cancer ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33030667

RESUMO

BACKGROUND: Previous findings regarding declines in cognitive functioning among patients with breast cancer (BC) before and after chemotherapy have been inconsistent. The present study explored the effect of BC and cancer-related chemotherapies on cognitive functioning. METHODS: A cross-sectional design was adopted to compare BC patients before their chemotherapy treatment, BC patients 3 ~ 9 months after the completion of chemotherapy, and noncancer controls. Evaluations of cognitive functioning included subjective and objective dimensions, with focus on memory, executive functioning, attention, and language. ANCOVA and Pearson's correlation analysis were used to examine the relationship among cancer, chemotherapy, cognitive performance, and psychological distress. RESULTS: After adjustment for intelligence quotient, anxiety, and depression, we found significant differences in the Semantic Association of Verbal Fluency between post-chemotherapy (C/T) patients and noncancer controls. Specifically, post-C/T patients scored lower than controls (p = 0.03, η2 = 0.07). No significant differences were found in other objective cognitive measures. However, both subjective and objective cognitive scores were significantly associated with depression, anxiety, and fatigue. In BC patients, levels of anxiety were positively correlated with measures of executive function. Among pre-C/T patients, self-perceived interference by fatigue was positively associated with better performances in some of the objective cognitive measures. CONCLUSION: Our findings suggest cognitive impairments in the domain of executive functioning among patients with BC who received chemotherapy. Providing relevant suggestions or strategies of managements for these negative consequences may help increase the long-term quality of life of patients with BC.

19.
Carbohydr Polym ; 250: 116842, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33049811

RESUMO

The chitosan/okra powder/nano-silicon aerogel composite films were prepared by casting method and their physicochemical properties and structural characterization were studied. The results showed that the composite film had good mechanical properties, barrier properties and optical properties. The composite film has strong flexibility. The surface glossiness of C/D/S1.5:1:0.1 film was 14.4Gu. As for the antibacterial activity, all the composite films had strong antibacterial activity against Gram-negative (E. coli) and Gram-positive (S. aureus), and the inhibition zone of C/D/S1.5:1:0.10 against E. coli reached 551.96 mm2, the inhibition zone for S. aureus was 350.29 mm2. The composite film had uniform, non-porous, continuous and dense surface characteristics. The structural characterization confirmed that there was good compatibility between chitosan, okara powder and nano-silicon aerogel. In summary, the composite films had excellent performance and structure, which promoted the research of functional packaging films.

20.
Artigo em Inglês | MEDLINE | ID: mdl-33052650

RESUMO

Silicon (Si) has been considered as the most potential anode material for next-generation high-energy density lithium-ion batteries (LIBs) because of its extremely high theoretical capacity. However, the performance deterioration caused by volume change and low electrical conductivity of active Si particles greatly limit its commercial use. Here, we designed a nonstoichiometric TiOx-coated Si anode with a litchi-like structure, in which Si-Ti and Si-O dual bonds are expected to form between the Si core and TiOx shell. This unique structure plays a major role in preventing the volume expansion and improving the electrical conductivity of the Si anode. The as-prepared TiOx-coated Si anode could exhibit excellent cycling stability after 1000 cycles at 1000 mA g-1 with a relatively small capacity decay rate of ∼0.04% per cycle, which can be comparable to most of the modified Si anodes in references. This strategy of surface regulating on the Si anode could be extended to other electrodes with large volume expansion during cycling in LIBs for achieving competitive electrochemical properties.

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