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• Heterotypic Ub reagents were obtained by CAET strategy with high efficiency. • The reagents identify heterotypic Ub-interacting and modifying proteins simultaneously. • Sequential release of two groups of proteins was completed by using urea and reductant. • Proteomic profiling facilitates future investigations of heterotypic Ub chains. Heterotypic ubiquitin (Ub) chains have emerged as fundamental components in a wide range of cellular processes. The integrative identification of Ub-interacting proteins (readers) and Ub-modifying enzymes (writers and erasers) that selectively recognize and regulate heterotypic ubiquitination may provide crucial insights into these processes. In this study, we employed the bifunctional molecule-assisted (CAET) strategy to develop a type of disulfide bond-activated heterotypic Ub reagents, which allowed to enrich heterotypic Ub-interacting proteins and modifying enzymes simultaneously. The sequential release of readers which are non-covalently bound and writers or erasers which are covalently conjugated by using urea and reductant, respectively, combined with label-free quantitative (LFQ) MS indicated that these heterotypic Ub reagents would facilitate future investigations into functional roles played by heterotypic Ub chains. [ABSTRACT FROM AUTHOR]

A higher diet quality has been associated with lower environmental impacts, but not consistently. Considering the cultural diversity of dietary habits and the heterogeneity of socioeconomic development in China, we aimed to evaluate the association between diet quality and environmental impacts across demographic subgroups and regions. This study used dietary consumption data from the China Health Nutrition Survey 2011. Diet quality was measured with the Chinese Healthy Eating Index 2016 (CHEI2016). Diet-related environmental impact (Greenhouse Gas Emissions (GHGE), Total Water Use (TWU), and Land Use (LU)) were estimated using the Chinese Food Life Cycle Assessment Database. Multilevel regression models were used to quantify the association of the CHEI2016 score and the diet-related environmental impacts across heterogeneous population subgroups. A one-standard deviation increase in CHEI2016 score was associated with an increase of 9.7% in GHGE, 9.1% in TWU, and 6.4% in LU. This occurs because increasing the consumption of under-consumed foods (dairy products and fruit), partially offsets the environmental benefits of reduced meat consumption. Demographic subgroups characterized by either higher educated or a higher income exhibited a larger proportion of animal-based foods within their diet, consequently leading to higher diet-related environmental impacts. When expressed per standard deviation increase in CHEI2016, the dietary environmental impacts rose fastest in the Metropolitan area and slowest in the Northeast. Diets with higher CHEI2016 scores are associated with higher diet-related environmental impacts among Chinese adults but this varies per region. The development of sustainable diet strategies needs to account for potential trade-off between the health and environmental goals, and dietary habits of consumers in different regions and subpopulations. [ABSTRACT FROM AUTHOR]

Over the past decade or two, the concept has emerged of using multiple types of weak interactions simultaneously to enhance the mechanical properties of elastomers. These weak interactions include physical entanglements, hydrogen bonds, metal-coordination bonds, dynamic covalent bonds, and ionic bonds. The combination of entanglements and ionic bonding has been minimally explored and is particularly exciting because of the broad application space for polyelectrolytes. In this work, a constitutive model framework is developed to describe the response of elastomers with both ionic bonds and entanglements. We formulate a micromechanical model that couples together chain stretching, ionic bond slipping, and entanglement evolution. The ionic bonds provide toughness by enabling plastic deformation in comparison to covalently crosslinked material and add strength compared to a linear polymer. Evolution of the entanglement density is taken as a key mechanism that can govern stiffness, toughness, and self-recovery in elastomers. The model is used to match bulk polyelectrolytes with different fractions of ionic components under a variety of loading histories. The variations in material parameters are then used to help understand the relative importance of different governing mechanisms in the bulk polymers. We show that the theoretical framework can explain our experimental uniaxial tensile experimental results for polyelectrolytes. This model can help to design better material with high stiffness and toughness. We expect that our model can be extended to explain the mechanical behavior of other polyelectrolytes and other soft materials with a wide range of dynamic bonds. • Model entanglement evolution driven by shear stress and chain diffusion. • Ionic bonds found to provide strength and dissipate energy without stiffness loss. • Establishes constitutive model coupling entanglement and ionic crosslink effects. [ABSTRACT FROM AUTHOR]

Sucralose and acesulfame-potassium consumption alters gut microbiota in rodents, with unclear effects in humans. We examined effects of three-times daily sucralose- and acesulfame-potassium-containing diet soda consumption for 1 (n = 17) or 8 (n = 8) weeks on gut microbiota composition in young adults. After 8 weeks of diet soda consumption, the relative abundance of Proteobacteria, specifically Enterobacteriaceae, increased; and, increased abundance of two Proteobacteria taxa was also observed after 1 week of diet soda consumption compared with sparkling water. In addition, three taxa in the Bacteroides genus increased following 1 week of diet soda consumption compared with sparkling water. The clinical relevance of these findings and effects of sucralose and acesulfame-potassium consumption on human gut microbiota warrant further investigation in larger studies. Clinical trial registration: NCT02877186 and NCT03125356. [ABSTRACT FROM AUTHOR]

Objective This study aimed to investigate human fetal exposure to non-nutritive sweeteners (NNS) by analyzing amniotic fluid and umbilical cord blood. Study Design Concentrations of four NNS (acesulfame-potassium [ace-K], saccharin, steviol glucuronide, and sucralose) were measured in amniotic fluid (n = 13) and cord blood samples (n = 15) using liquid chromatography-mass spectrometry. Amniotic fluid samples were obtained for research purposes at the time of term elective cesarean birth or clinically indicated third trimester amnioreduction at Mercy Hospital for Women (Melbourne, Australia). All except four women were in the fasting state. Cord blood samples were obtained from an independent cohort of newborns whose mothers were enrolled in a separate clinical trial at the National Institutes of Health. Results Ten of 13 amniotic fluid samples contained at least one NNS (ace-K, saccharin, steviol glucuronide, and/or sucralose). Maximum amniotic fluid NNS concentrations of ace-K, saccharin, steviol glucuronide, and sucralose were 78.9, 55.9, 93.5, and 30.6 ng/mL, respectively. Ace-K and saccharin were present in 100% and 80% of the cord blood samples, with maximal concentrations of 6.5 and 2.7 ng/mL, respectively. Sucralose was not detected and steviol glucuronide was not measurable in any of the cord blood samples. Conclusion Our results provide evidence of human transplacental transmission of NNS. Based on results predominantly obtained from rodent models, we speculate that NNS exposure may adversely influence the offsprings' metabolic health. Well-designed, prospective clinical trials are necessary to understand the impact of NNS intake during pregnancy on human development and long-term health. Key Points NNS consumption during pregnancy has increased in recent years. Maternal NNS intake during pregnancy is associated with preterm birth and higher infant weight gain in epidemiologic studies. In rodents, in utero NNS exposure induces metabolic abnormalities in mothers and their offspring, alters offspring gut microbiota composition, and promotes sweet taste preference in adulthood. It is presently unknown whether and to what degree maternal NNS ingestion in humans leads to direct in utero exposure. This study provides the first evidence of in utero NNS exposure in humans and highlights the urgent need to investigate clinical consequences of early life NNS exposure on metabolism, weight, taste preference, and general health. [ABSTRACT FROM AUTHOR]

In radiotherapy, air-filled ion chamber detectors are ubiquitously used in routine dose measurements for treatment planning. However, its use has been restricted by intrinsic low spatial resolution barriers. We developed one procedure for patient-specific quality assurance (QA) in arc radiotherapy by coalescing two adjacent measurement images into a single image to improve spatial resolution and sampling frequency, and investigated how different spatial resolutions affect the QA results. PTW 729 and 1500 ion chamber detectors were used for dosimetric verification via coalescing two measurements with 5 mm-couch shift and the isocenter, and only isocenter measurement, which we call coalescence and standard acquisition (SA). Statistical process control (SPC), process capability analysis (PCA), and receiver operating characteristic (ROC) curve were used to compare the performance of the two procedures in determining tolerance levels and identifying clinically relevant errors. By analyzing 1256 γ values calculated on interpolated data points, our results indicated that detector 1500 showed higher averages in coalescence cohorts at different tolerance criteria and the dispersion degrees were spread out smaller. Detector 729 yielded a slightly lower process capability of 0.79, 0.76, 1.10, and 1.34, but detector 1500 exhibited somewhat different results of 0.94, 1.42, 1.19, and 1.60 in magnitude. The results of SPC individual control chart showed that cases in coalescence cohorts with γ values lowering its lower control limit (LCL) were greater than those in SA cohorts for detector 1500. A combination of the width of multi-leaf collimator (MLC) leaf, the cross-sectional area of the single detector, and the spacing between adjacent detectors might lead to discrepancies in percent γ values across diverse spatial resolution scenarios. The accuracy of reconstructed volume dose is mainly determined by the interpolation algorithm used in dosimetric systems. The magnitude of filling factor in the ion chamber detectors determined its ability to detect dose deviations. SPC and PCA results indicated that coalescence procedure could detect more potential failure QA results than SA while enhancing action thresholds. [ABSTRACT FROM AUTHOR]

Aim: Dietary nitrate (NO3−) supplementation increases nitric oxide bioavailability and can enhance exercise performance. We investigated the distribution and metabolic fate of ingested NO3− at rest and during exercise with a focus on skeletal muscle. Methods: In a randomized, crossover study, 10 healthy volunteers consumed 12.8 mmol 15N‐labeled potassium nitrate (K15NO3; NIT) or potassium chloride placebo (PLA). Muscle biopsies were taken at baseline, at 1‐ and 3‐h post‐supplement ingestion, and immediately following the completion of 60 maximal intermittent contractions of the knee extensors. Muscle, plasma, saliva, and urine samples were analyzed using chemiluminescence to determine absolute [NO3−] and [NO2−], and by mass spectrometry to determine the proportion of NO3− and NO2− that was 15N‐labeled. Results: Neither muscle [NO3−] nor [NO2−] were altered by PLA. Following NIT, muscle [NO3−] (but not [NO2−]) was elevated at 1‐h (from ~35 to 147 nmol/g, p < 0.001) and 3‐h, with almost all of the increase being 15N‐labeled. There was a significant reduction in 15N‐labeled muscle [NO3−] from pre‐ to post‐exercise. Relative to PLA, mean muscle torque production was ~7% greater during the first 18 contractions following NIT. This improvement in torque was correlated with the pre‐exercise 15N‐labeled muscle [NO3−] and the magnitude of decline in 15N‐labeled muscle [NO3−] during exercise (r = 0.66 and r = 0.62, respectively; p < 0.01). Conclusion: This study shows, for the first time, that skeletal muscle rapidly takes up dietary NO3−, the elevated muscle [NO3−] following NO3− ingestion declines during exercise, and muscle NO3− dynamics are associated with enhanced torque production during maximal intermittent muscle contractions. [ABSTRACT FROM AUTHOR]

The reduction pathway of nitrate (NO3−) and nitrite (NO2−) to nitric oxide (NO) contributes to regulating many physiological processes. To examine the rate and extent of dietary nitrate absorption and its reduction to nitrite, we supplemented rat diets with Na15NO3-containing water (1 g/L) and collected plasma, urine and several tissue samples. We found that plasma and urine showed 8.8- and 11.7-fold increases respectively in total nitrate concentrations in 1-day supplementation group compared to control. In tissue samples—gluteus, liver and eyes—we found 1.7-, 2.4- and 4.2-fold increases respectively in 1-day supplementation group. These increases remained similar in 3-day supplementation group. LC–MS/MS analysis showed that the augmented nitrate concentrations were primarily from the exogenously provided 15N-nitrate. Overall nitrite concentrations and percent of 15N-nitrite were also greatly increased in all samples after nitrate supplementation; eye homogenates showed larger increases compared to gluteus and liver. Moreover, genes related to nitrate transport and reduction (Sialin, CLC and XOR) were upregulated after nitrate supplementation for 3 days in muscle (Sialin 2.3-, CLC1 1.3-, CLC3 2.1-, XOR 2.4-fold) and eye (XOR 1.7-fold) homogenates. These results demonstrate that dietary nitrate is quickly absorbed into circulation and tissues, and it can be reduced to nitrite in tissues (and likely to NO) suggesting that nitrate-enriched diets can be an efficient intervention to enhance nitrite and NO bioavailability. [ABSTRACT FROM AUTHOR]

Light aromatics are important organic building blocks in the chemical industry which can be produced by catalytic fast pyrolysis (CFP) of biomass. In this work, wet torrefaction pretreatment (WTP) was employed to improve the quality of bamboo by synergistic effect of deoxygenation and demineralization. Then, CFP was employed to produce bio-aromatics by using zeolite (e.g. HZSM-5, HY, Al-MCM-41, and USY) as catalyst. Results showed that WTP temperature (180–260 °C) had more significant influence on the mass yields of torrefied products compared to WTP duration (30–150 min). The maximum deoxygenation rate was 49.36% at WTP conditions of 260 °C and 150 min, and the maximum demineralization rate followed the order of 96.29% (K) > 94.54% (Na) > 90.33% (Mg) > 89.22% (Ca). Among the five types of zeolite catalyst tested, HZSM-5 (25) was the best catalyst to obtain bio-aromatics due to its unique pore size and reasonable acidity. The maximum yield of aromatics (25.46 ×107 a.u./mg) was obtained at the WTP temperature of 220 °C, biomass-to-catalyst ratio of 3:1, and CFP temperature of 850 °C. Toluene was the more favored monocyclic aromatic hydrocarbon formed during CFP compared to xylene and benzene. [Display omitted] • Novel approach (WTP coupled with CFP) was developed to produce bio-aromatics. • Synergistic deoxygenation and deminerization of WTP was investigated. • Maximum deoxygenation and deminerization rates by WTP were 49.36% and over 90%, respectively. • Optimal operation parameters of WTP and CFP were investigated. • Toluene was more favorable to be formed than xylene and benzene. [ABSTRACT FROM AUTHOR]

Background. Radiotherapy is one of the major strategies for treating tumors, and it inevitably causes damage to relevant tissues and organs during treatment. Radiation-induced heart disease (RIHD) refers to radiation-induced cardiovascular adverse effects caused by thoracic radiotherapy. Currently, there is no uniform standard in the treatment of RIHD. Methods. In our group study, by administering a dose of 4 Gy radiation, we established a radiation injured cardiomyocyte model and explored the regulatory relationship between tanshinone IIA and p38 MAPK in cardiomyocyte injury. We assessed cell damage and proliferation using clonogenic assay and lactate dehydrogenase (LDH) release assay. The measures of antioxidant activity and oxidative stress were conducted using superoxide dismutase (SOD) and reactive oxygen species (ROS). The apoptosis rate and the relative expression of apoptotic proteins were conducted using flow cytometry and western blot. To assess p38 and p53 expressions and phosphorylation levels, western blot was performed. Results. Experimental results suggested that tanshinone IIA restored cell proliferation in radiation-induced cardiomyocyte injury (∗ ∗ P < 0.01), and the level of LDH release decreased (∗ P < 0.05). Meanwhile, tanshinone IIA could decrease the ROS generation induced by radiation (∗ ∗ P < 0.01) and upregulate the SOD level (∗ ∗ P < 0.01). Again, tanshinone IIA reduced radiation-induced cardiomyocyte apoptosis (∗ ∗ P < 0.01). Finally, tanshinone IIA downregulated radiation-induced p38/p53 overexpression (∗ ∗ ∗ P < 0.001). Conclusions. The treatment effects of tanshinone IIA against radiation-induced myocardial injury may be through the regulation of the p38/p53 pathway. [ABSTRACT FROM AUTHOR]

Photocaged, activity‐based ubiquitin (Ub) probes (Ub‐ABPs) have been developed for the time‐resolved probing of deubiquitinating enzyme (DUB) activities, but many Ub‐ABPs are still challenging to photocage because their warheads (e.g. propargylamide (PA) or dehydroalanine (Dha)) are difficult to temporally block and activate. Here, we describe a new C‐terminal backbone modification strategy for the construction of photocaged Ub‐ABPs in which a light‐sensitive group is placed at the backbone amide bond of the Ub Gly75. This strategy enabled the facile generation of cell‐permeable photocaged Ub‐PA and Dha probes that could be activated to capture DUBs after photo‐irradiation, and were used to profile DUBs in cells under specially designed conditions (e.g. in cells experiencing oxidative stress) or DUBs with isopeptide linkage selectivity. This backbone modification strategy is anticipated to provide a general solution for the development of photocaged Ub ABPs bearing any warheads for DUB profiling. [ABSTRACT FROM AUTHOR]

Photocaged, activity‐based ubiquitin (Ub) probes (Ub‐ABPs) have been developed for the time‐resolved probing of deubiquitinating enzyme (DUB) activities, but many Ub‐ABPs are still challenging to photocage because their warheads (e.g. propargylamide (PA) or dehydroalanine (Dha)) are difficult to temporally block and activate. Here, we describe a new C‐terminal backbone modification strategy for the construction of photocaged Ub‐ABPs in which a light‐sensitive group is placed at the backbone amide bond of the Ub Gly75. This strategy enabled the facile generation of cell‐permeable photocaged Ub‐PA and Dha probes that could be activated to capture DUBs after photo‐irradiation, and were used to profile DUBs in cells under specially designed conditions (e.g. in cells experiencing oxidative stress) or DUBs with isopeptide linkage selectivity. This backbone modification strategy is anticipated to provide a general solution for the development of photocaged Ub ABPs bearing any warheads for DUB profiling. [ABSTRACT FROM AUTHOR]