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Sophora davidii is an ideal material for studying the response to low phosphorus (P) because of its strong adaptability to low-P habitats. However, to date, there has been no research on S. davidii under low-P stress. In this paper, the differentially expressed genes (DEGs) of S. davidii were studied on days 3 and 9 of low-P treatment by transcriptome sequencing and analysed with GO and KEGG analyses. Under low-P stress, the contents of antioxidants (POD, SOD and CAT), osmotic adjusters (soluble protein and proline) and anthocyanin increased. Under low-P and normal-P conditions, 323 (209 and 114 of whose expression was upregulated and downregulated, respectively) and 504 DEGs (280 and 224 of whose expression was upregulated and downregulated, respectively) were found in S. davidii on days 3 and 9, respectively. The analysis of transcriptomics data revealed certain aspects of genes regulation under low-P stress. First, several key candidate genes, such as Orphans, GNAT, bZIP, MYB, AP2-EREBP, NAC and WRKY genes, were predicted to determine tolerance to low-P stress. Second, four pathways (starch and sucrose metabolism; plant hormone signal transduction; phenylpropanoid biosynthesis; and alanine, aspartate and glutamate metabolism) were correlated with low-P stress and were highly differentially regulated in two time treatments. These results provide new insights into the complex mechanisms of the low-P response in S. davidii or even other plant species. [ABSTRACT FROM AUTHOR]

Temperature has been studied in relation to many health outcomes. However, few studies have explored its effect on the risk of hospital admission for rheumatoid arthritis (RA). A distributed lag non-linear model (DLNM) was used to analyze associations between mean temperature, diurnal temperature range (DTR), temperature change between neighboring days (TCN), and daily admissions for RA from 2015 to 2019 in Anqing, China. Subgroup analyses based on age, gender, rheumatoid factors, and admission route were performed. In total, 1456 patients with RA were hospitalized. Regarding the cumulative-lag effects of extreme cold temperature (5th percentile = 3℃), the risks of admissions for RA were increased and highest at lag 0–11 (RR = 2.68, 95% CI: 1.23–5.86). Exposing to low (5th percentile = 1.9℃) and high (95th percentile = 14.2℃) DTRs both had increased risks of RA admission, with highest RRs of 1.40 (95% CI: 1.03–1.91) and 1.24 (95% CI: 1.0–1.53) at lag 0 day, respectively. As for TCN, the marginal risk of admission in RA patients was found when exposed to high TCN (95th percentile = 2.9℃) with the largest single-day effect at lag 10 (RR = 1.11, 95% CI: 1.01–1.23). In subgroup analyses, females were more susceptible to extreme cold temperature, low and high DTRs, and high TCN. In regard to extreme cold temperature, significant risk of hospital admission in females only appeared at lag 2 (RR = 1.48, 95% CI: 1.02–2.15) and lag 0–2 (RR = 2.35, 95% CI: 1.11–4.95). It is clear that RA patients exposed to changing temperature may increase risks of admission. [ABSTRACT FROM AUTHOR]

The site selectivity for lysine conjugation on a native protein is difficult to control and characterize. Here, we applied mass spectrometry to examine the conjugation kinetics of Trastuzumab-IgG (Her-IgG) and α-lactalbumin under excess linker concentration ([L]0) based on the modified Michaelis–Menten equation, in which the initial rate constant per amine (kNH2 = Vmax/NH2/KM) was determined by the maximum reaction rate (Vmax/NH2) under saturated accessible sites and initial amine–linker affinity (1/KM). Reductive amination (RA) displayed 3–4 times greater Vmax/NH2 and a different panel of conjugation sites than that observed for N-hydroxysuccinimide ester (NHS) chemistry using the same length of polyethylene glycol (PEG) linkers. Moreover, faster conversion power rendered RA site selectivity among accessible amine groups and a greater tunable range of linker/protein ratio for aldehyde-linkers compared to those of the same length of NHS-linkers. Single conjugation with high yield or poly-conjugations with site homogeneity was demonstrated by controlling [L]0 or gradual addition to minimize the [L]0/KM ratio. Formaldehyde, the shortest aldehyde-linker with the greatest 1/KM, exhibited the highest selectivity and was shown to be a suitable probe to predict conjugation profile of aldehyde-linkers. Four linkers on the few probe-predicted hot spots were elucidated by kinetically controlled RA with conserved drug efficacy when conjugated with the payload. This study provides insights into controlling factors for homogenous and predictable amine bioconjugation. [ABSTRACT FROM AUTHOR]

Dynamic changes in growth characteristics and endogenous hormone contents in the leaves and roots of Sophora davidii seedlings under low-phosphorus stress were studied to provide a reference for further study of the internal regulatory mechanism of the response strategy of this species to low-phosphorus stress. Normal phosphorus (0.5 mmol KH2PO4, NP) and low-phosphorus (0.005 mmol KH2PO4, LP) levels and different treatment times were applied to study growth characteristics, phosphorus utilization and hormone contents in the leaves and roots of potted Sophora davidii by tissue culture and sand culture. The results first showed that compared with NP, LP significantly decreased the plant height, leaf length, leaf width, leaf area, leaf perimeter and root–shoot ratio by 20.10%, 21.08%, 22.73%, 51.33%, 24.94% and 18.92%, respectively. LP decreased the total root length and root dry weight, and increased the root surface area, average root diameter, root tip number, root volume and dry weight of the aerial part on day 9, but these effects were not significant. Second, compared with NP, LP significantly decreased P contents in the aerial part and roots and P uptake efficiency in the aerial part and roots on day 9 by 23.33%, 53.89%, 14.04% and 58.06%, respectively. LP significantly increased the P utilization efficiency and leaf acid phosphatase (ACP) activity on day 9 by 82.79% and 84.38%, respectively. LP increased root ACP activity on day 9, but the effect was not significant. Third, compared with NP, LP significantly decreased abscisic acid (ABA), cytokinin (CTK) and strigolactone (SL) contents in leaves by 21.52%, 36.65% and 45.86%, respectively, and significantly increased gibberellin (GA) contents in roots by 28.92% on day 9. LP decreased GA contents in leaves and CTK contents in roots and increased indole-3-acetic acid (IAA) contents in leaves and roots and ABA and SL contents in roots on day 9, but these effects were not significant. Correlation analysis indicated that endogenous hormone contents in Sophora davidii leaves and roots under different treatment conditions had certain correlations with growth characteristics. In conclusion, Sophora davidii can improve its P utilization efficiency by changing growth characteristics and endogenous hormones to enhance its adaptive response to low-phosphorus stress. [ABSTRACT FROM AUTHOR]

Purpose: To compare hepatobiliary phase (HBP) images obtained 10 and 20 min after Gd-EOB-DTPA-enhanced MRI for liver function assessment in clinic on 3.0 T MR imaging. Methods: 103 patients were separated into four groups: 38 patients for the normal liver function (NLF) group, 33 patients for the liver cirrhosis with Child-Pugh A (LCA) group, 21 patients for the liver cirrhosis with Child-Pugh B group, and 11 patients for a liver cirrhosis with Child-Pugh C group. T1 relaxation times (T1rt) were measured on T1 mapping and reduction rates of T1rt (rrT1rt) were calculated. HBP images were obtained at the 10- and 20-min mark after Gd-EOB-DTPA enhancement. Results: T1rt on pre-enhancement imaging showed no significant difference ( p > 0.05) among all four groups. T1rt for both the 10-min HBP and the 20-min HBP showed a significant difference ( p < 0.05) among all groups, but showed no significant difference ( p > 0.05) between the NLF group and the LCA group. T1rt and rrT1rt showed no significant difference ( p > 0.05) between 10-min HBP and 20-min HBP among all groups. The ROC analysis on 10-min HBP and 20-min HBP showed a lower diagnostic performance between NLF group and LCA group (AUC from 0.532 to 0.582), but high diagnostic performance (AUC from 0.788 to 1.000) among others group. Conclusions: In comparing 10-min HBP and 20-min HBP T1 mapping after Gd-EOB-DTPA enhancement, our results suggest that 10-min HBP T1 mapping is a feasible option for quantitatively assessing liver function. [ABSTRACT FROM AUTHOR]

Objectives: To compare hepatobiliary phase (HBP) images obtained at 10 and 20 min after Gd-EOB-DTPA-enhanced MRI for assessment of liver function in rabbit fibrosis model on 3.0 T MR imaging. Methods: 34 animals were separated into three groups: 5 for a control group, 14 for a mild fibrosis group, and 15 for a severe fibrosis group based on pathological proof. T1 relaxation times (T1rt) were measured on T1 mapping and reduction rates of T1rt (rrT1rt) were calculated. HBP images were obtained at 10 and 20 min after Gd-EOB-DTPA enhancement. Indocyanine green retention rates at 15 min (ICG R15) were performed for all animals. Results: T1rt on pre-enhancement imaging showed no significant difference ( p > 0.05) among all groups. T1rt on 10 min HBP and 20 min HBP showed significant difference ( p < 0.05) among all groups. T1rt and rrT1rt in three groups showed no-significant difference ( p > 0.05) between 10 min HBP and 20 min HBP. T1rt on both 10 and 20 min HBP showed significant correlation with ICG R15 ( p < 0.05); rrT1rt on both 10 min HBP and 20 min HBP showed significant inverse correlation with ICG R15 ( p < 0.05). Conclusions: Comparing 10 min HBP and 20 min HBP T1 mapping after Gd-EOB-DTPA enhancement, our results suggest that 10 min HBP T1 mapping is feasible for quantitatively assessing liver function. [ABSTRACT FROM AUTHOR]

Material integration by wafer bonding and layer transfer is one of the main approaches to increase functionality of semiconductor devices and to enhance integrated circuits (IC) performance. Even though most mismatches such as different lattice constants betweeen bonding materials present no obstacle for wafer direct bonding, thermal stresses caused by thermal mismatches must be minimized by low temperature bonding to avoid debonding, sliding or cracking. In order to achieve a strong bond at low temperatures, two approaches may be adopted: 1) Bonding at room temperature by hydrogen bonding of OH, NH, or FH terminated surfaces followed by polymerization to form covalent bonds. Within this approach the key is to remove the by-products of the reaction at the bonding interface. 2) Direct formation of a covalent bond between clean surfaces without adsorbents in ultra high vacuum conditions. Low temperature bonding allows bonding processed wafers for technology integration. Layer transfer requires uniform thinning of one wafer of a bonded pair. The most promising technology involves a buried embrittled region by hydrogen implantation. A layer with a thickness corresponding to the hydrogen implantation depth is then transferred onto a bonded desired substrate by either splitting due to internal gas pressure or by forced peeling as long as the bonding energy is higher than the fracture energy in the embrittled region at the layer transfer temperature. This approach is quite generic in nature and may be applied to almost all materials. We have found that B+H co-implantation and/or H implantation at high temperatures can significantly lower the splitting temperature. However, the wafer temperature during H implantation has to be within a temperature window that is specific for each material. The experimentally determined temperature windows for some semiconductors and single crystalline oxides will be given. [ABSTRACT FROM AUTHOR]