Conformer-specific photochemistry imaged in real space and time

[Figure: see text].

Methionine supplementation during a hydrogen peroxide challenge alters components of insulin signaling and antioxidant proteins in subcutaneous adipose explants from dairy cows

Enhanced postruminal supply of methionine (Met) during the peripartal period alters protein abundance of insulin, AA, and antioxidant signaling pathways in subcutaneous adipose tissue (SAT). Whether SAT is directly responsive to supply of Met and can induce molecular alterations is unknown. Our objective was to examine whether enhanced Met supply during an oxidative stress challenge in vitro alters insulin, AA, inflammation, and antioxidant signaling-related protein networks. Four late-lactation Holstein cows (average 27.0 kg of milk per day) were used for SAT collection. Tissue was incubated in duplicate for 4 h in a humidified incubator with 5% CO₂ at 37°C according to the following experimental design: control medium with an "ideal" profile of essential AA (CTR; Lys:Met 2.9:1), CTR plus 100 μM H₂O₂ (HP), or CTR with greater Met supply plus 100 μM H₂O₂ (HPMET; Lys:Met 2.5:1). Molecular targets associated with insulin signaling, lipolysis, antioxidant nuclear factor, erythroid 2 like 2 (NFE2L2), inflammation, and AA metabolism were determined through reverse-transcription quantitative PCR and western blotting. Data were analyzed using the MIXED procedure of SAS 9.4 (SAS Institute Inc.). Among proteins associated with insulin signaling, compared with CTR, HP led to lower abundance of phosphorylated AKT serine/threonine kinase (p-AKT) and solute carrier family 2 member 4 (SLC2A4; insulin-induced glucose transporter). Although incubation with HPMET restored abundance of SLC2A4 to levels in the CTR and upregulated abundance of fatty acid synthase (FASN) and phosphorylated 5'-prime-AMP-activated protein kinase (p-AMPK), it did not alter p-AKT, which remained similar to HP. Among proteins associated with AA signaling, compared with CTR, challenge with HP led to lower abundance of phosphorylated mechanistic target of rapamycin (p-MTOR), and HPMET did not restore abundance to CTR levels. Among inflammation-related targets studied, incubation with HPMET led to greater protein abundance of nuclear factor kappa B subunit p65 (NFKB-RELA). The response in NFKB observed with HPMET was associated with a marked upregulation of the antioxidant transcription regulator NFE2L2 and the antioxidant enzyme glutathione peroxidase 1 (GPX1). No effects of treatment were detected for mRNA abundance of proinflammatory cytokines or antioxidant enzymes, underscoring the importance of post-transcriptional regulation. Overall, data indicated that short-term challenge with H₂O₂ was particularly effective in reducing insulin and AA signaling. Although a greater supply of Met had little effect on those pathways, it seemed to restore the protein abundance of the insulin-induced glucose transporter. Overall, the concomitant upregulation of key inflammation and antioxidant signaling proteins when a greater level of Met was supplemented to oxidant-challenged SAT highlighted the potential role of this AA in regulating the inflammatory response and oxidant status. Further studies should be conducted to assess the role of postruminal supply of Met and other AA in the regulation of immune, antioxidant, and metabolic systems in peripartal cow adipose tissue.

Imaging the short-lived hydroxyl-hydronium pair in ionized liquid water

[Figure: see text].

Bioleaching of tellurium from mine tailings by indigenous Acidithiobacillus ferrooxidans

Tellurium (Te) is a scarce and valuable metalloid, which can be found in some mine tailings. In this work, an indigenous Acidithiobacillus ferrooxidans strain was used to leach Te from mine tailings collected in the Shimian Te mine region, China. Under the optimized conditions of initial pH of 2·0, pulp density of 4% and temperature of 30°C, 47·77% of Te can be dissolved after 24 days of bioleaching. The leaching of Te by different systems such as bioleaching, Ferric ion (Fe(III)) leaching and acid leaching was compared. The results showed that the leaching behaviour of Te is similar to that of sulphur in sulphide minerals, that is, Fe(III) first oxidizes telluride (Te(-II)) in minerals to elemental Te, and then elemental Te can be oxidized by bacteria to Te(IV) and Te(VI). Besides, it was also showed by scanning electron microscope observation and Fourier transform infrared spectroscopy analysis of the ore sample before and after bioleaching that some bedded structure covered on the surface of the ore after bioleaching acting as a reaction compartment, and the changing of active groups indicated a possible attachment between bacteria and ore. There is an indirect mechanism involved in bioleaching of Te.

MDA5 attenuate autophagy in chicken embryo fibroblasts infected with IBDV

1. The role of melanoma differentiation-associated protein 5 (MDA5) in infectious bursal disease virus (IBDV)-induced autophagy was studied in chicken embryos.2. Chicken embryo fibroblasts (CEF) were used as the research model and small interfering RNA (siRNA), western blot, indirect enzyme-linked immunosorbent assay (ELISA), real-time fluorescence quantitative polymerase chain reaction (PCR) and transmission electron microscopy were used to detect autophagy, IBDV replication, CEF damage, and activation of both MDA5 and its signalling pathway.3. The results showed that CEF infected with IBDV activated the intracellular MDA5 signalling pathway and caused autophagy via inactivation of the AKT/mTOR pathway. While autophagy promotes IBDV proliferation, MDA5 weakens IBDV-induced CEF autophagy thus inhibiting IBDV replication and protecting CEF cells.4. The results indicated that chMDA5 can be activated by IBDV and attenuate CEF autophagy caused by IBDV infection, thereby inhibiting IBDV replication. This study provided a foundation for further exploring the relationship between viruses, autophagy and the pathogenic mechanism of the MDA5 pathway involved in IBDV.

High urinary excretion rate of glucose attenuates serum uric acid level in type 2 diabetes with normal renal function

AIMS/INTRODUCTION

The relationship between urinary excretion rate of glucose (UEGL) and uric acid (UA) metabolism in adults with type 2 diabetes (T2D) remains unclear to date. This study aimed to investigate the relationships of UEGL with serum UA (SUA), urinary excretion rate of uric acid (UEUA), and renal clearance of uric acid (CLUA) in adults with T2D. We hypothesised that high UEGL increases UA excretion, which in turn leads to lower SUA.

MATERIALS AND METHODS

This was a cross-sectional study of 635 inpatients with T2D recruited between 2018 and 2019. The relationships of UEGL with UEUA, CLUA, and hyperuricaemia were assessed using analysis of covariance and multivariate regression analysis.

RESULTS

Patients in the higher quartile of UEGL tended to have lower SUA levels than those in the lower quartile. In contrast, patients in the higher quartile of UEGL tended to have higher CLUA (p for trend < 0.0001), and a similar trend was observed for UEUA. In adjusted multivariable linear regression model, UEGL was negatively correlated with SUA (β = - 0.023, 95% CI - 0.034 to - 0.013, p < 0.0001). However, positive correlations of UEGL with UEUA (β = 0.046, 95% CI 0.018-0.074, p = 0.001) and CLUA (β = 0.063, 95% CI 0.042-0.085, p < 0.0001) were found. Furthermore, consistent significant inverse associations were observed between quartiles of UEGL and hyperuricaemia in the adjusted multivariate logistic regression model.

CONCLUSIONS

A high UEGL level was positively correlated with UEUA and CLUA. Moreover, it was inversely associated with SUA level, and a consistently increased UEGL level reduced the risk of hyperuricaemia in patients with T2D.

Dysbiosis of intestinal microbiota in early life aggravates high-fat diet induced dysmetabolism in adult mice

BACKGROUND

Accumulating evidence have shown that the intestinal microbiota plays an important role in prevention of host obesity and metabolism disorders. Recent studies also demonstrate that early life is the key time for the colonization of intestinal microbes in host. However, there are few studies focusing on possible association between intestinal microbiota in the early life and metabolism in adulthood. Therefore the present study was conducted to examine whether the short term antibiotic and/or probiotic exposure in early life could affect intestinal microbes and their possible long term effects on host metabolism.

RESULTS

A high-fat diet resulted in glucose and lipid metabolism disorders with higher levels of visceral fat rate, insulin-resistance indices, and leptin. Exposure to ceftriaxone in early life aggravated the negative influences of a high-fat diet on mouse physiology. Orally fed TMC3115 protected mice, especially those who had received treatment throughout the whole study, from damage due to a high-fat diet, such as increases in levels of fasting blood glucose and serum levels of insulin, leptin, and IR indices. Exposure to ceftriaxone during the first 2 weeks of life was linked to dysbiosis of the fecal microbiota with a significant decrease in the species richness and diversity. However, the influence of orally fed ceftriaxone on the fecal microbiota was limited to 12 weeks after the termination of treatment. Of note, at week 12 there were still some differences in the composition of intestinal microbiota between mice provided with high fat diet and antibiotic exposure and those only fed a high fat diet.

CONCLUSIONS

These results indicated that exposure to antibiotics, such as ceftriaxone, in early life may aggravate the negative influences of a high-fat diet on the physiology of the host animal. These results also suggest that the crosstalk between the host and their intestinal microbiota in early life may be more important than that in adulthood, even though the same intestinal microbes are present in adulthood.

Gas kinetic flux solver based high-order finite-volume method for simulation of two-dimensional compressible flows

In this work, a high-order gas kinetic flux solver (GKFS) is developed for simulation of two-dimensional (2D) compressible flows. Different from the conventional gas kinetic scheme, which uses the local integral solution to the Boltzmann equation to reconstruct the numerical fluxes of macroscopic governing equations, the GKFS evaluates the numerical fluxes by the local asymptotic solution to the Boltzmann equation. This local asymptotic solution consists of the equilibrium distribution function and its substantial derivative at the cell interface. To achieve high-order accuracy in the simulation, the substantial derivative is discretized by a difference scheme with second-order accuracy in time and fourth-order accuracy in space, which results in a polynomial of the equilibrium distribution function at different locations and time levels. The Taylor series expansion is then introduced to simplify this polynomial. As a result, a simple high-order accurate local asymptotic solution to the Boltzmann equation is obtained and the numerical fluxes of macroscopic governing equations are given explicitly. A series of numerical examples are presented to validate the accuracy and capability of the developed high-order GKFS. Numerical results demonstrate that the high-order GKFS can achieve the desired accuracy on both the quadrilateral mesh and the triangular mesh and it outperforms the second-order counterpart.

[Analysis of maternal mortality trend and age-period-cohort model in China from 1992 to 2017]

Objective: To understand the trend of maternal mortality in China from 1992 to 2017, and to evaluate the effects of age, period and cohort of maternal mortality by using the age-period-cohort (APC) model. Methods: The data of maternal mortality in China from 1992 to 2017 were collected from the Global Burden of Disease project. The maternal mortality rate was adopted to describe the trend of death. The APC model and the estimable function algorithm were used to evaluate the impact of age, period and birth cohort factors on maternal mortality risk in China. Results: From1992 to 2017, the maternal mortality rate in China fluctuated slightly and then continued to decline and finally increased slightly. During this period, the net drift was -10.00% per year (95%CI:-10.92% to -9.08% per year), and all the local drifts were lower than zero in all age groups of 10-54 years old (P<0.05). The results of the APC model analysis showed that the maternal mortality risk of women in their life stage showed a trend of rapid decrease, then a slow climb and finally a rapid increase. The period relative risk and cohort relative risk of maternal mortality both showed a monotonous decreasing trend. Conclusion: From 1992 to 2017, the maternal mortality rate in China generally shows a downward trend, and the risk of maternal mortality has significant age, period and cohort effects.

Transcriptomic investigation of embryonic pectoral muscle reveals increased myogenic processes in Shitou geese compared to Wuzong geese

1.Embryonic stages before birth are crucial for poultry muscle development, as this determines muscle mass in adulthood. This study characterised the distinction in embryonic pectoral muscle development between Wuzong (WZE, small) and Shitou (STE, large) geese (two indigenous goose breeds in Guangdong Province, China) at embryonic days 15 (E15), 23 (E23) and the day of hatching (P1) to gain insights into the regulatory mechanisms of muscle development.2.The results showed that STE had significantly higher myofibre density during E15-P1 and had significantly larger myofibre diameter at E15 than WZE. By RNA-sequencing analysis, 19 507 genes were detected, and 7121 differentially expressed genes (DEGs) were identified.3.Gene expression distinctions between breeds began increasing from E23, and WZE had different gene expression profiles compared to STE. A GO analysis of DEGs indicated that myo-genes involved at E15 may influence distinct pectoral muscle development characteristics between WZE and STE. The RT-qPCR results were consistent with the RNA-sequencing analysis. Four muscle structure protein coding genes (MYL2, MYL3, TNNI2 and TNNC2 and three other functional genes (CAV3, CACNA1S and NOS1) were identified in a predicted interaction network. These functional genes may interact with muscle structural protein coding genes to regulate embryonic pectoral muscle development in WZE and STE geese.4.The study revealed that STE and WZE had divergent embryonic pectoral muscle development patterns and these differences may begin before E15.

Driver-passenger communicative stress and psychological distress among Chinese bus drivers: the mediating effect of job burnout

BACKGROUND

This study aimed to investigate the relationship between driver-passenger communicative stress and psychological distress among bus drivers, as well as whether job burnout mediates the effect of driver-passenger communicative stress on psychological distress.

METHODS

A questionnaire consisting of a 12-item version of the General Health Questionnaire (GHQ-12), a one-item driver-passenger communicative stress scale, the Maslach Burnout Inventory-General Survey (MBI-GS), as well as sociodemographic and work factors, was distributed to 310 bus drivers in Shanghai, of which 307 completed it (99.0% response rate). A parallel multiple mediation model with bootstrap approach, was calculated to test the mediating effect.

RESULTS

Driver-passenger communicative stress, emotional exhaustion and cynicism were positively associated with psychological distress. Communicative stress was significantly positively linked with two of the three dimensions of burnout (emotional exhaustion and cynicism) and dependent variable. Emotional exhaustion and cynicism were positively associated with the dependent variable. The results indicate that emotional exhaustion and cynicism partially mediated the effect of communicative stress on psychological health, and that 60.0% of this effect can be explained by mediating effects, in which emotional exhaustion and cynicism weighed 63.2% and 36.8%, respectively.

CONCLUSIONS

Communicative stress had effects on psychological distress among Chinese bus drivers, and job burnout was a mediator in this relationship.

Quantitative agreement between dynamical rocking curves in ultrafast electron diffraction for x-ray lasers

Electron diffraction through a thin patterned silicon membrane can be used to create complex spatial modulations in electron distributions. By precisely varying parameters such as crystallographic orientation and wafer thickness, the intensity of reflections in the diffraction plane can be controlled and by placing an aperture to block all but one spot, we can form an image with different parts of the patterned membrane, as is done for bright-field imaging in microscopy. The patterned electron beams can then be used to control phase and amplitude of subsequent x-ray emission, enabling novel coherent x-ray methods. The electrons themselves can also be used for femtosecond time resolved diffraction and microscopy. As a first step toward patterned beams, we demonstrate experimentally and through simulation the ability to accurately predict and control diffraction spot intensities. We simulate MeV transmission electron diffraction patterns using the multislice method for various crystallographic orientations of a single crystal Si(001) membrane near beam normal. The resulting intensity maps of the Bragg reflections are compared to experimental results obtained at the Accelerator Structure Test Area Ultrafast Electron Diffraction (ASTA UED) facility at SLAC. Furthermore, the fraction of inelastic and elastic scattering of the initial charge is estimated along with the absorption of the membrane to determine the contrast that would be seen in a patterned version of the Si(001) membrane.

Alterations in immune and antioxidant gene networks by gamma-d-glutamyl-meso-diaminopimelic acid in bovine mammary epithelial cells are attenuated by in vitro supply of methionine and arginine

Nucleotide-binding oligomerization domain (NOD)-like receptor 1 (NOD1) is a cytosolic pattern recognition receptor with a crucial role in the innate immune response of cells triggered by the presence of compounds such as gamma-d-glutamyl-meso-diaminopimelic acid (iE-DAP) present in the peptidoglycan of all gram-negative and certain gram-positive bacteria. Methionine (Met) and arginine (Arg) are functional AA with immunomodulatory properties. In the present study, we aimed to assess the effect of increased Met and Arg supply on mRNA abundance of genes associated with innate immune response, antioxidant function, and AA metabolism during iE-DAP challenge in bovine mammary epithelial cells (BMEC). Primary BMEC (n = 4 per treatment) were precultured in modified medium for 12 h with the following AA formulations: ideal profile of AA (control), increased Met supply (incMet), increased Arg supply (incArg), or increased supply of Met plus Arg (incMetArg). Subsequently, cells were challenged with or without iE-DAP (10 μg/mL) for 6 h. Data were analyzed as a 2 × 2 × 2 factorial using the MIXED procedure of SAS 9.4. Greater mRNA abundance of NOD1, the antioxidant enzyme SOD1, and AA transporters (SLC7A1 and SLC3A2) was observed in the incMet cells after iE-DAP stimulation. Although increased Met alone had no effect, incMetArg led to greater abundance of the inflammatory cytokine IL-6, and the antioxidant enzyme GPX1 after iE-DAP stimulation. The increased Arg alone downregulated NOD1 after iE-DAP stimulation, coupled with a downregulation in the AA transporters mRNA abundance (SLC7A1, SLC7A5, SLC3A2, and SLC38A9), and upregulation in GSS and KEAP1 mRNA abundance. Overall, the data indicated that increased supply of both Met and Arg in the culture medium were more effective in modulating the innate immune response and antioxidant capacity of BMEC during in vitro iE-DAP stimulation.

Leukocyte immunoglobulin-like receptor A3 is increased in IBD patients and functions as an anti-inflammatory modulator

Growing evidence shows that a homozygous 6·7-kb deletion of the novel anti-inflammatory molecule leukocyte immunoglobulin-like receptor A3 (LILRA3) is associated with many autoimmune disorders. However, its effects on pathogenesis of inflammatory bowel disease (IBD) have yet not been clarified. LILRA3 is mainly expressed in monocytes, whereas its effects on biological behaviors of monocytes have not been systematically reported. In our study, to investigate the association between LILRA3 polymorphism and IBD susceptibility, LILRA3 polymorphism was assessed in 378 IBD patients and 509 healthy controls. Quantitative real time PCR (qRT-PCR), Western blot and immunohistochemistry (IHC) were employed to detect the LILRA3 expression in IBD patient blood and intestinal samples. The human U937 monocyte cell line was employed to establish LILRA3 over-expressing cells and the effects of LILRA3 on the biological behaviors of U937 cells were systematically explored. Although no association of the polymorphism with IBD development was found, LILRA3 expression was markedly increased in IBD patients compared with healthy controls. Over-expression of LILRA3 in monocytes led to significant decreases in secretion of interferon (IFN)-γ, tumor necrosis factor (TNF)-α and interleukin (IL)-6. Additionally, LILRA3 abated monocyte migration by reducing the expression of several chemokines and enhanced monocyte phagocytosis by increasing CD36 expression. Furthermore, LILRA3 promoted monocyte proliferation through a combination of Akt and extracellular receptor kinase/mitogen-activated protein kinase (Erk/MEK) signaling pathways. We report for the first time, to our knowledge, that LILRA3 is related to IBD and functions as an anti-inflammatory modulator in U937 cells.