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Childhood adversity is associated with abnormalities in brain structure, but this association has not been tested for childhood unpredictability, one form of adversity. We studied whether abnormalities in gray matter volume (GMV) could be a mechanism linking childhood unpredictability and psychopathology, over and above the effect of childhood trauma.
Participants were 158 right-handed healthy young adults (aged 17–28 years, M = 22.07, s.d. = 2.08; 66.46% female) who underwent structural magnetic resonance imaging measurements and provided retrospective reports of childhood unpredictability. The anxiety and depression subscales of the self-report Brief Symptom Inventory-53 were used to index psychopathology.
Whole-brain voxel-based morphometric analyses showed that after controlling for the effect of childhood trauma, childhood unpredictability was correlated with greater GMV in bilateral frontal pole, bilateral precuneus, bilateral postcentral gyrus, right hemisphere of fusiform, and lingual gyrus, and left hemisphere of ventrolateral prefrontal cortex as well as occipital gyrus. Greater GMV in bilateral frontal pole, bilateral precuneus, and bilateral postcentral gyrus mediated associations between unpredictability and symptoms of depression and anxiety.
The findings suggest that childhood unpredictability could exact unique effects on neural development, over and above the effect of childhood trauma. These findings are relevant for understanding the occurrence of psychopathology following childhood unpredictability and have implications for intervention.
Sepsis is a clinical syndrome characterised by a severe disorder of pathophysiology caused by infection of pathogenic micro-organisms. The addition of antioxidant micronutrient therapies such as thiamine to sepsis treatment remains controversial. This study explored the effect of thiamine on the prognosis of patients with sepsis. This study was a retrospective study involving patients with sepsis from the Medical Information Mart for Intensive Care IV. Patients were divided into two groups, the thiamine received group (TR) and the thiamine unreceived group (TUR), according to whether they were supplemented with thiamin via intravenous while in the intensive care unit (ICU). The primary outcome was ICU mortality. The association between thiamine and outcome was analysed using the Cox proportional hazards regression model, propensity score matching (PSM), generalised boosted model-based inverse probability of treatment weighting (IPTW) and doubly robust estimation. A total of 11 553 sepsis patients were enrolled in this study. After controlling for potential confounders using Cox regression models, the TR group had a statistically significantly lower ICU mortality risk than the TUR group. The hazard ratio of ICU mortality for the TR group was 0·80 (95 % CI 0·70, 0·93). We obtained the same results after using PSM, IPTW and doubly robust estimation. Supplementation with thiamine has a beneficial effect on the prognosis of patients with sepsis. More randomised controlled trials are needed to confirm the effectiveness of thiamine supplementation in the treatment of sepsis.
Clay often has severe detrimental impacts on cement-based materials. Therefore, it is necessary to investigate the mechanism causing the deterioration to improve the service life of cement-based materials. Based on accurate dimensional analysis, a mechanism that influences clay is proposed: the intercalation of the side chains of superplasticizer molecules in the interlayer space of the clay. To lessen this harmful effect, a new clay-resistant admixture (CRA) possessing cationic groups of small molecular size was synthesized through a novel dimensional design. The length and width of the side chains of this superplasticizer molecule were 9.50–17.50 and 0.25–0.40 nm, respectively, with a radius of ~3.74 nm in solvent, which is larger than the interlayer spacing of montmorillonite (i.e. 1.09–2.14 nm). The longitudinal and latitudinal lengths of the CRA molecule were 0.468 and 9.456 nm, respectively, ensuring intercalation in the interlayer of montmorillonite. The increase in interlayer spacing of the clay was 0.364 nm following addition of polycarboxylate superplasticizer (PCE) plus CRA and 0.632 nm following addition of PCE, which suggests that the CRA plays the role of a ‘sacrificial agent’ that is preferentially intercalated into the interlayer space of clay to further prevent the side chains of the superplasticizer molecules from entering the interlayer. The aim of this study was to propose a suitable means of synthesizing a new CRA to address the impact of clay through dimensional design and mechanism analysis, which contributes to the theoretical study and technological improvement of cement-based materials.
Internet gaming disorder (IGD) is becoming a matter of concern around the world. However, the neural mechanism underlying IGD remains unclear. The purpose of this paper is to explore the differences between the neuronal network of IGD participants and that of recreational Internet game users (RGU).
Imaging and behavioral data were collected from 18 IGD participants and 20 RGU under a probability discounting task. The independent component analysis (ICA) and graph theoretical analysis (GTA) were used to analyze the data.
Behavioral results showed the IGD participants, compared to RGU, prefer risky options to the fixed ones and spent less time in making risky decisions. In imaging results, the ICA analysis revealed that the IGD participants showed stronger functional connectivity (FC) in reward circuits and executive control network, as well as lower FC in anterior salience network (ASN) than RGU; for the GTA results, the IGD participants showed impaired FC in reward circuits and ASN when compared with RGU.
These results suggest that IGD participants were more sensitive to rewards, and they were more impulsive in decision-making as they could not control their impulsivity effectively. This might explain why IGD participants cannot stop their gaming behaviors even when facing severe negative consequences.
Little is known about the effect of persistent depressive symptoms on the trajectory of cognitive decline.
We aimed to investigate the longitudinal association between the duration of depressive symptoms and subsequent cognitive decline over a 10-year follow-up period.
The English Longitudinal Study of Ageing cohort is a prospective and nationally representative cohort of men and women living in England aged ≥50 years. We examined 7610 participants with two assessments of depressive symptoms at wave 1 (2002–2003) and wave 2 (2004–2005), cognitive data at wave 2 and at least one reassessment of cognitive function (wave 3 to wave 7, 2006–2007 to 2014–2015).
The mean age of the 7610 participants was 65.2 ± 10.1 years, and 57.0% were women. Of these, 1157 (15.2%) participants had episodic depressive symptoms and 525 participants (6.9%) had persistent depressive symptoms. Compared with participants without depressive symptoms at wave 1 and wave 2, the multivariable-adjusted rates of global cognitive decline associated with episodic depressive symptoms and persistent depressive symptoms were faster by –0.065 points/year (95% CI –0.129 to –0.000) and –0.141 points/year (95% CI –0.236 to –0.046), respectively (P for trend < 0.001). Similarly, memory, executive and orientation function also declined faster with increasing duration of depressive symptoms (all P for trend < 0.05).
Our results demonstrated that depressive symptoms were significantly associated with subsequent cognitive decline over a 10-year follow-up period. Cumulative exposure of long-term depressive symptoms in elderly individuals could predict accelerated subsequent cognitive decline in a dose-response pattern.
Garnets, omphacite and the minerals of a clinopyroxene/amphibole/plagioclase symplectite in UHP eclogites from Yingshan, Dabieshan have been investigated by TEM and Micro-FTIR. TEM reveals that the predominant microstructures in eclogites and symplectite-forming minerals are chain multiplicity faults (CMFs), dislocation substructures, clusters of water molecules up to ∼50 nm in diameter and recrystallized grains ∼1.75 μm in diameter. This indicates dynamic recrystallization of omphacite, probably during an eclogite-facies metamorphic episode. The deformation structures in symplectite-forming minerals were produced by plastic deformation related to an amphibolite-facies retrograde metamorphic event. CMFs described in the present work demonstrate the existence of an infrequent ½<011> (010) slip system for P2/n omphacite from an UHP eclogite sample from Dabieshan. The frequent occurrence of CMFs in omphacite suggests that they indicate an important deformation mechanism in omphacite and shows that this slip system plays a significant role in the deformation and recovery of eclogite. The hydrous components of deformed minerals may cause plastic deformation of the rocks by dislocation movement and accelerate retrograde metamorphism. Micro-FTIR results show that all the garnets and omphacites contain structural water occurring as hydroxyl groups (OH) or water (H2O). The structural water contents in omphacite range from 110—710 ppm and in garnet from 0—180 ppm. Water released during decompression might supply an early-stage retrograde metamorphic fluid.
3D microarchitected metamaterials exhibit unique, desirable properties influenced by their small length scales and architected layout, unachievable by their solid counterparts and random cellular configurations. However, few of them can be used in high-temperature applications, which could benefit significantly from their ultra-lightweight, ultrastiff properties. Existing high-temperature ceramic materials are often heavy and difficult to process into complex, microscale features. Inspired by this limitation, we fabricated polymer-derived ceramic metamaterials with controlled solid strut size varying from 10-µm scale to a few millimeters with relative densities ranging from as low as 1 to 22%. We found that these high-temperature architected ceramics of identical 3D topologies exhibit size-dependent strength influenced by both strut diameter and strut length. Weibull theory is utilized to map this dependency with varying single strut volumes. These observations demonstrate the structural benefits of increasing feature resolution in additive manufacturing of ceramic materials. Through capitalizing upon the reduction of unit strut volumes within the architecture, high-temperature ceramics could achieve high specific strength with only fraction of the weight of their solid counterparts.
Leucine plays an important role in promoting muscle protein synthesis and muscle remodelling. However, what percentage of leucine is appropriate in creep feed and what proteome profile alterations are caused by dietary leucine in the skeletal muscle of piglets remain elusive. In this case, we applied isobaric tags for relative and absolute quantitation to analyse the proteome profile of the longissimus dorsi muscles of weanling piglets fed a normal leucine diet (NL; 1·66 % leucine) and a high-leucine diet (HL; 2·1 % leucine). We identified 157 differentially expressed proteins between these two groups. Bioinformatics analysis of these proteins exhibited the suppression of oxidative phosphorylation and fatty acid β-oxidation, as well as the activation of glycolysis, in the HL group. For further confirmation, we identified that SDHB, ATP5F1, ACADM and HADHB were significantly down-regulated (P<0·01, except ATP5F1, P<0·05), whereas the glycolytic enzyme pyruvate kinase was significantly up-regulated (P<0·05) in the HL group. We also show that enhanced muscle protein synthesis and the transition from slow-to-fast fibres are altered by leucine. Together, these results indicate that leucine may alter energy metabolism and promote slow-to-fast transitions in the skeletal muscle of weanling piglets.
Vascular smooth muscle cell migration is a microscopic in vivo process where specific cells crawl in order to partake in crucial physiological functions relating to embryonic development, wound healing, and tissue development. Abnormalities of cell migration result in pathologies such as tumor metastasis, angiogenesis, chronic inflammation, and various immune response dysfunctions. The mechanism behind cellular migration and the role of intracellular proteins in the instigation of cell directionality remains poorly understood without effective biomedical device available. The development of microfluidic biochips technologies enable detection, sample preparation and treatment on one single chip. We are reporting the design and fabrication of a novel microfluidic trip for guiding and quantifying cell migrations. The chip featured micropillar arrays imbedded in a multichannel microfluidic chip, where cell migration can be guided by utilizing the characteristics of laminar flow. Non-blending layers of fluid injected through the multi-channel device simulated a wounded edge across a monolayer of cells by limiting flow of trypsin, a serine protease, to half of the main channel, promoting cell migration in a desired direction. Control over cell directionality allows for the measurement and analysis of mechanical forces generated during cell migration in relation to migratory responses from intracellular protein inhibition. The micro-fluidic chip template was designed and manufactured using photolithography techniques. Polydimethylsiloxane (PDMS) served as the bulk material of the two compromising chip layers (channels and pillars), which were subsequently aligned and adhered to form the device. It was confirmed through both computer simulation and experimentation that the through optimized arrangement of the chip design, this device can effectively hold laminar flows of trypsin and cell media. Thus, this microfluidic device allows the user to simultaneously acquire force data during cell migration and observe migratory patterns to ultimately gain a better understanding of the underlying mechanisms of cell migration and directionality.
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