Whether nonalcoholic fatty liver disease (NAFLD) is associated with an increased risk of mortality remains controversial. The present study aimed to clarify this issue. A systematic search of PubMed ...and Embase was conducted through October 2018. Studies providing risk estimates of NAFLD and mortality were included. A random-effects model was employed to calculate summary risk estimates. Subgroup analyses were performed to identify potential effect modifiers. Fourteen studies, involving 498501 subjects and 24234 deaths, were included. Patients with NAFLD were found to be at an elevated risk of all-cause mortality compared with those without hazard ratio (HR) = 1.34; 95% confidence interval (CI) 1.17-1.54). The significantly positive association between NAFLD and all-cause mortality could not be modified by age, sex, follow-up duration, and adjustment for body mass index, diabetes, smoking or hypertension (all P
> 0.05), and remained in sensitivity analyses. No significant associations of NAFLD with CVD (HR = 1.13; 95% CI 0.92-1.38) and cancer (HR = 1.05; 95% CI 0.89-1.25) mortality were found. In conclusion, NAFLD is a predictor of increased all-cause mortality but not CVD and cancer mortality. These findings have important implications for decision making in public health and clinical practice, and highlight the urgency of developing effective treatments for NAFLD.
Hydrogels are crosslinked hydrophilic polymers that can absorb a large amount of water. By their hydrophilic, biocompatible and highly tunable nature, hydrogels can be tailored for applications in ...bioanalysis and biomedicine. Of particular interest are DNA-based hydrogels owing to the unique features of nucleic acids. Since the discovery of the DNA double helical structure, interest in DNA has expanded beyond its genetic role to applications in nanotechnology and materials science. In particular, DNA-based hydrogels present such remarkable features as stability, flexibility, precise programmability, stimuli-responsive DNA conformations, facile synthesis and modification. Moreover, functional nucleic acids (FNAs) have allowed the construction of hydrogels based on aptamers, DNAzymes, i-motif nanostructures, siRNAs and CpG oligodeoxynucleotides to provide additional molecular recognition, catalytic activities and therapeutic potential, making them key players in biological analysis and biomedical applications. To date, a variety of applications have been demonstrated with FNA-based hydrogels, including biosensing, environmental analysis, controlled drug release, cell adhesion and targeted cancer therapy. In this review, we focus on advances in the development of FNA-based hydrogels, which have fully incorporated both the unique features of FNAs and DNA-based hydrogels. We first introduce different strategies for constructing DNA-based hydrogels. Subsequently, various types of FNAs and the most recent developments of FNA-based hydrogels for bioanalytical and biomedical applications are described with some selected examples. Finally, the review provides an insight into the remaining challenges and future perspectives of FNA-based hydrogels.
Display omitted
•The prepared hydrogel showed a great self-healing ability and spontaneously self-healed within 15 s.•The prepared hydrogel was highly transparent, with transmittance reaching as high ...as 90%.•The developed hydrogel sensor was able to sense very subtle external pressure such as water drop.•The sensor worked stably on the detection of human motions such as finger, knee or elbow movements.
Wearable sensors have emerged as favored novel devices for human healthcare. Current sensors, however, suffer from low sensitivity, non-transparency, and lack of self-healing ability. In this study, we synthesized a polyvinyl alcohol/cellulose nanofibril (PVA/CNF) hydrogel with dual-crosslinked networks for highly transparent, stretchable, and self-healing pressure and strain sensors. The hydrogel contains dynamic borate bonds, metal–carboxylate coordination bonds, and hydrogen bonds, all of which contribute to the hydrogel’s superior dimensional stability, mechanical strength and flexibility, and spontaneous self-healing ability as compared to traditional PVA hydrogels. The developed hydrogel has a moderate modulus of 11.2 kPa, and a high elongation rate of 1900%. It spontaneously self-heals within 15 s upon contact without any external stimuli, has a high transmittance of over 90%, and has excellent compatibility with human fibroblasts. The capacitive sensor developed based on the PVA/CNF hydrogel has high sensitivity to very subtle pressure changes, such as small water droplets. When used as a strain sensor, it was capable of detecting and monitoring various human motions such as finger, knee, elbow, and head movements, breathing, and gentle tapping. The developed hydrogel and sensors not only show great potential in electronic skin, personal healthcare, and wearable devices, but may also inspire the development of transparent, intelligent skin-like sensors.
Display omitted
•Core-double-shell architecture was designed as efficient HER and OER electrocatalysts.•Cobalt phosphide and NiFe-LDH were used as representative HER and OER catalysts.•The ...architecture consist of core–shell porous carbon fiber (CFC@EC) and TMCs.•Lattice distortions were created in the TMCs by CFC@EC, facilitating the exposure of active sites.•Enhanced performance is due to the strong electronic interaction between the hybrids.
Different transition metal compounds (TMCs) nanostructures grown on conductive substrates have been considered as promising self-supportive non-precious electrocatalysts for electrochemical water splitting, but extremely challenging to develop facile and generalized approaches for rational design and enhancing their catalytic properties. Herein, we develop a general strategy to boost the hydrogen and oxygen evolution reactions (HER and OER) performance of TMCs by designing monolith electrocatalyst architectures. The monoliths comprises of TMCs integrated on carbon fiber cloth core–shell (CFC@EC) structure. The CFC@EC allows the creation of numerous lattice distortions and strong electronic interactions between CFC@EC and metal cations of the TMCs. Such lattice distortions exposes more active sites in CFC@EC/TMCs compared to the pristine CFC coated TMCs (CFC/TMC). Cobalt phosphide (CoP) nanowires and NiFe-LDH coated on CFC@EC exhibits the optimized HER and OER activities. Overall water splitting device assembled based on the optimized HER and OER electrodes also achieve low overall potential of 1.53 V at 10 mA cm−2. More importantly, we further experimentally verify that the integration of Ni3N and Ni3S2, CoS2, NiCo-LDH, NiMn-LDH with CFC@EC also reveal similar improved performance, providing a general and valuable strategy into the design of other self-supporting electrocatalysts for water splitting and beyond.
Herein, we report a nongenetic and real-time approach for imaging protein dimerization on living cell surfaces by aptamer recognition and proximity-induced DNA assembly. We use the aptamer specific ...for the receptor monomer as a recognition probe. When receptor dimerization occurs, the dimeric receptors bring two aptamer probes into close proximity, thereby triggering dynamic DNA assembly. The proposed approach was successfully applied to visualize dimerization of Met receptor and transforming growth factor-β type II receptor. This approach allows us to image the two states (monomer/dimer) of a receptor protein on living cell surfaces in real time, opening a universal method for further investigation of protein dimerization and the corresponding activation processes in signal transduction.
Abstract
Coronal mass ejections (CMEs) are violent ejections of magnetized plasma from the Sun that can trigger geomagnetic storms, endanger satellite operations, and destroy electrical ...infrastructures on the Earth. After systematically searching Sun-as-a-star spectra observed by the Extreme Ultraviolet Variability Experiment on board the Solar Dynamics Observatory (SDO) from 2010 May to 2022 May, we identified eight CMEs associated with flares and filament eruptions by analyzing the blue-wing asymmetry of the O
iii
52.58 nm line profiles. Combined with images simultaneously taken by the 30.4 nm channel of the Atmospheric Imaging Assembly on board SDO, the full velocity and propagation direction for each of the eight CMEs are derived. We find a strong correlation between geomagnetic indices (
Kp
and Dst) and the angle between the CME propagation direction and the Sun–Earth line, suggesting that Sun-as-a-star spectroscopic observations at extreme-ultraviolet wavelengths can potentially help to improve the prediction accuracy of the geoeffectiveness of CMEs. Moreover, an analysis of synthesized long-exposure Sun-as-a-star spectra implies that it is possible to detect CMEs from other stars through blue-wing asymmetries or blueshifts of spectral lines.
Abstract The default mode network (DMN) is a set of functionally connected brain regions which shows deactivation (task-induced deactivation, TID) during a cognitive task. Evidence shows an ...age-related decline in task-load-related modulation of the activity within the DMN during cognitive tasks. However, the effect of age on the functional coupling within the DMN and their relation to cognitive performance has hitherto been unexplored. Using functional magnetic resonance imaging, we investigated functional connectivity within the DMN in older and younger subjects during a working memory task with increasing task load. Older adults showed decreased connectivity and ability to suppress low frequency oscillations of the DMN. Additionally, the strength of the functional coupling of posterior cingulate (pCC) with medial prefrontal cortex (PFC) correlated positively with performance and was lower in older adults. pCC was also negatively coupled with task-related regions, namely the dorsolateral PFC and cingulate regions. Our results show that in addition to changes in canonical task-related brain regions, normal aging is also associated with alterations in the activity and connectivity of brain regions within the DMN. These changes may be a reflection of a deficit in cognitive control associated with advancing age that results in deficient resource allocation to the task at hand.
Display omitted
•Three dimensional fluffy nanofibrous scaffold was prepared by CO2 escaping foaming.•Shih-kebab structure was successfully introduced onto 3D nanofibrous scaffold.•The developed 3D ...nanofibrous scaffolds possess low density, high surface area and porosity.•Fibroblast Cells were able to migrate into the inner of the scaffold effectively.
Electrospun nanofibrous scaffolds are highly recognized in tissue engineering since they can mimic the structure of extracellular matrix (ECM). However, the nanofibers fail to resemble the three dimensional geometry of organs, and the surface nanotopography of collagen fibrils in ECM. In order to mimic the structure of ECM in both macroscale (3D geometry) and microscale (surface nanotopography), an ingenious approach was developed in this study. Electrospun nanofibers collected in ethanol bath was soaked in CO2 saturated ethanol and subsequently foamed in a water bath, due to the escaping of CO2 gas. This simple green method takes the advantage of solubility difference of carbon dioxide (CO2) in ethanol and water, and is applicable to different materials. The foamed fluffy polycaprolactone (PCL) nanofibrous scaffolds achieved a low bulk density of 0.041 g/cm3 and a high porosity of 95.3%. To resemble the surface nanotopography of ECM, shish-kebab structure was introduced onto the fluffy PCL nanofibers by controlled crystallization. The shish-kebab structures greatly enhanced the surface area of scaffolds from 6.9 m2/g for 2D PCL to 10.9 m2/g for 3D SK-PCL. In addition, 3T3 fibroblast cell culture results confirmed that the cells interacted strongly with the 3D fluffy nanofibers and migrated into the inner area of the scaffolds rapidly. Moreover, human fibroblast cell culture results confirmed further enhancement in cell attachment and proliferation on the fluffy shish-kebab structured nanofibrous scaffolds, which indicates the developed biomimetic 3D scaffolds have high potential to be used for 3D tissue regeneration.
Abstract
Background and Hypothesis
Social competition affects human behaviors by inducing psychosocial stress. The neural and genetic mechanisms of individual differences of cognitive-behavioral ...response to stressful situations in a competitive context remain unknown. We hypothesized that variation in stress-related brain activation and genetic heterogeneity associated with psychiatric disorders may play roles towards individually differential responses under stress.
Study Design
A total of 419 healthy subjects and 66 patients with schizophrenia were examined functional magnetic resonance imaging during working memory task including social competition stressors. We explored the correlation between stress-induced brain activity and individual working memory performance. The partial least squares regression was performed to examine the genetic correlates between stress-related activity and gene expression data from Allen Human Brain Atlas. Polygenic risk score (PRS) was used to assess individual genetic risk for schizophrenia.
Study Results
Greater suppression of bilateral striatal activity was associated with better behavioral improvement in working memory manipulation under social competition (left: rPearson = −0.245, P = 4.0 × 10−6, right: rPearson = −0.234, P = 1.0 × 10−5). Genes transcriptionally related to stress-induced activation were linked to genetic risk for schizophrenia (PFDR < 0.005). Participants with decreased accuracy under social competition exhibited higher PRS of schizophrenia (t = 2.328, P = .021). Patients with schizophrenia showed less suppressed striatal activity under social stress (F = 13.493, P = 3.5 × 10−4).
Conclusions
Striatal activity change and genetic risk for schizophrenia might play a role in the individually behavioral difference in working memory manipulation under stress.
PDF
