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Abstract In this paper, brilliant cresyl blue (BCB) was selected as a sonosensitizer. The sonodynamic damage to human serum albumin (HSA) in the presence of BCB and the mechanism were studied by means of fluorescence and absorption spectra. Firstly, BCB could quench the intrinsic fluorescence of HSA obviously and the quenching mechanism was static quenching due to the formation of HSA-BCB complex. The results of the displacement experiments and the molecular modeling suggested that the binding site of BCB on HSA was site I, and hydrophobic forces and hydrogen bonds played major roles in the interaction between HSA and BCB. Secondly, the damage of HSA induced by the combined effects of ultrasonic irradiation and BCB was more efficient than that only BCB or ultrasound irradiation, which confirmed that BCB had sonodynamic activity. The damage degree of HSA was positively correlated with reactive oxygen species (ROS) produced in the system, which indicated that ultrasound could activate BCB to produce ROS, and the kinds of ROS produced by the combined effects of ultrasonic irradiation and BCB were mainly hydroxyl free radical, singlet oxygen and superoxide anion radical. [ABSTRACT FROM AUTHOR]

In this study, the single and simultaneous interactions of theophylline and flavonoids with human serum albumin (HSA) were studied by multi-spectroscopic and molecular docking approaches. The influences of flavonoids on the binding constant ( K b ) and the binding distance ( r ) of theophylline bind to HSA were determined and the changes of HSA conformation caused by the synergies of theophylline and flavonoids were investigated. Because theophylline, rutin and baicalin are all bond to the same binding site, the competitive bind of theophylline and flavonoids to HSA leads to the reduction of the K a value of theophylline binding to HSA. The addition of rutin and baicalin can increase the value of r of theophylline binding to HSA, which further confirm the existence of the competitive bind of theophylline and flavonoids to HSA. Additionally, the results of synchronous fluorescence, three-dimensional fluorescence and circular dichroism spectra indicate that the presence of rutin and baicalin can give rise to the further changes of HSA conformation. These results suggest that the intake of flavonoid-rich food and beverages can increase the serum concentrations of theophylline and induce a high incidence of toxic symptom in clinic. [ABSTRACT FROM AUTHOR]

In this work, bovine serum albumin (BSA) and eosine B (EB) were selected as a model protein and sonosensitizer, respectively. The sonodynamic damage to protein in the presence of EB and its mechanism were studied by means of absorption and fluorescence spectra. The results indicated that the synergistic effects of ultrasound and EB can efficiently damage the BSA molecules, and the damage of protein could be mainly due to the generation of reactive oxygen species (ROS). The damage degree of protein increased with the increase of ultrasonic time and EB concentration because of the increased quantities of ROS. Hydroxyl free radical ( OH) was the major mediators of the ultrasound-inducing proteins damage in the presence of EB. In addition, the quantities of ROS from the diphenylcarbazide (DPCI)–EB solutions and the DPCI–fluorescein (FS) solutions with or without ROS scavengers were contrasted, respectively. The results show that FS mainly produce OH, but the quantities of ROS in the presence of FS were lower than those of EB, which indicates that the nitro and bromine substituent groups on the benzene ring of FS increase the quantity of ROS, but do not change the kinds of ROS. [ABSTRACT FROM AUTHOR]

The sonodynamic damage to protein in the presence of methylene blue (MB) and the various influencing factors including ultrasonic irradiation time and MB concentration on the damage of protein were studied by fluorescence and absorption spectra. In addition, the mechanisms of the synergistic effects of ultrasound and MB were studied by oxidation–extraction photometry with several reactive oxygen species (ROS) scavengers. The results indicated that the damage of protein induced by the synergistic effects of ultrasound and MB were more serious than those that ultrasound or MB alone was applied. The damage of protein could be mainly due to the generation of ROS. The damage degree of protein increased with the increase of ultrasonic irradiation time and MB concentration because of the increased quantities of ROS generation. Both 1 O 2 and OH were the important mediators of the ultrasound-inducing protein damage in the presence of MB. [ABSTRACT FROM AUTHOR]

[Display omitted] • Investigating heavy rainfall and loose fill soil as primary natural triggers for sinkholes in non karst areas. • Identifying metro constructions and pipeline damages as major human-induced factors for urban sinkholes. • The Gray Relation Analysis method was used in sinkhole susceptibility mapping. • Risk assessment based on urban transportation system was conducted for enhanced sinkhole prevention. • A sinkhole risk identification framework employing InSAR and geophysical technologies was proposed. Urban sinkholes can cause subsidence damage to transportation infrastructures, building demolitions and even casualties when they occur suddenly. It is hence essential to identify their forming factors and analyze their spatial distribution features, so as to pave the way for sinkhole risk assessment and mitigation for urban sustainable development. Investigation of urban sinkholes poses a significant challenge because of the multi-factor's confusion, as well as the spatial uncertainties in susceptibility mapping due to urban renewal frequently. To address these issues, a comprehensive urban sinkhole risk assessment framework was proposed, and Shenzhen city in South China was selected as a case study area, where a lot of sinkholes occurred along with intensive human construction activities in recent years. Initially, the sinkhole susceptibility map was drawn using the grey relation analysis (GRA) method, incorporating the spatial information database of meteorology, geology, metro and pipeline systems, and then both the sinkhole density map and the time-varying land subsidence monitoring database were used to verify the accuracy of the sinkhole susceptibility map. Furthermore, the sinkhole risk assessment map in transportation system was subsequently drawn based on the susceptibility map, where the Interferometric Synthetic Aperture Radar (InSAR) and the advanced geophysical exploration technologies were employed to probe the potential sinkholes in critical risk areas. The conclusions reveal that the sinkhole susceptibility map based on GRA method demonstrates a promise in identifying the likelihood of urban sinkholes, and the risk assessment framework can be employed for the prevention and remediation of urban sinkholes, which contributes to an economical and efficient scheme for sinkhole detection, as well as transportation system resilience assessment at a city-wide scale. [ABSTRACT FROM AUTHOR]

Nifedipine (NDP) is used extensively for the clinical treatment of a number of cardiovascular diseases. Herein, the interaction between human serum albumin (HSA) and NDP and the influence of flavonoids, rutin and baicalin, on their binding properties were investigated in vitro by means of fluorescence and absorption spectroscopy. The fluorescence of HSA was quenched remarkably by NDP and the quenching mechanism was considered as static quenching by forming a complex. The results of thermodynamic parameters indicate that both hydrogen bonds and hydrophobic interactions play the main role in the binding process and the binding process was spontaneous. The binding distance between the amino acid residue of HSA and NDP is 2.608 nm, which indicates that the energy transfer from HSA to NDP can occur with high probability. The decreased association constants and the increased binding distance of NDP binding to HSA in the presence of flavonoids were both due to their competitive binding to the site I of HSA. The results obtained from synchronous fluorescence and three-dimensional fluorescence spectra showed that the interaction between HSA and NDP caused the conformational changes of HSA and the synergism effects of NDP and flavonoids induced the further conformational changes of HSA. [ABSTRACT FROM AUTHOR]

A new room temperature ionic liquid (RTIL) has been prepared by directly mixing InCl3 and 1-ethyl-3-methylimidazolium chloride (EMIC) under dry nitrogen atmosphere. The phase diagram of the binary system InCl3–EMIC was determined by DSC. Both Raman scattering and ab inito calculations indicate that InCl4− is the predominant indium-containing species in the ionic liquid. And it was further confirmed by NMR experiments. [Copyright &y& Elsevier]

T helper (Th17) cells play an important role in many autoimmune diseases. In this meta-analysis, we aimed to specify the proportion of Th17 cells and the levels of Th17-related cytokines in neuromyelitis optica spectrum disorders (NMOSD) patients, we did this meta-analysis. Using previously reported data from PubMed, EMBASE, and Web of Science and Cochrane, we explored the proportion of Th17 cells in CD4+ T cells in peripheral blood (PB) and the level of Th17-related cytokines, such as interleukin (IL)1β, IL6, IL17, IL21, IL22, IL23 and transforming growth factor -beta (TGFβ), in cerebrospinal fluid (CSF), plasma, and serum in NMOSD patients compared to control group and multiple sclerosis (MS) patients. In total, 38 trials were included for our analysis. Results showed that the proportion of Th17 cells was higher in NMOSD patients than in the control and MS groups. The levels of IL1β, IL6, IL17 and IL21 in CSF and plasma, and IL6, IL21, IL22, and IL23 in the serum were higher in NMOSD patients than in the control group. The levels of IL6 in CSF and serum and IL17 in plasma and serum were higher in NMOSD patients than in MS patients. The proportion of Th17 cells and the levels of Th17-related cytokines was increased in NMOSD patients compared with the control group and MS patients. The results of this meta-analysis indicated that Th17 cells and Th17-associated cytokines may play an essential role in the pathogenesis of NMOSD. PROSPERO registration: CRD42019128785. • The proportion of Th17 cells of NMOSD patients was higher than control and MS. • The levels of IL6 and IL21 in CSF, plasma and serum of NMOSD were higher than control. • The levels of IL17 and IL1β in CSF and plasma of NMOSD were higher than control. • The levels of IL23 in serum of NMOSD were higher than control. • The levels of IL6 in CSF and serum and IL17 in serum of NMOSD were higher than MS. [ABSTRACT FROM AUTHOR]

Highlights • A seven-color panel including CD34 and TdT was built to detect MRD in T-ALL. • The panel could be applied to >97% T-ALL patients independent of initial phenotype. • Only one MRD false-negative result occurred because of antigen shifts. • MRD positive detected by the panel at post-HSCT could effectively predict relapse. Abstract A seven-color panel was used to detect minimal residual disease (MRD) in T cell acute lymphoblastic leukemia (T-ALL) via flow cytometry (FCM). Its availability and clinical significance were studied in T-ALL patients with newly diagnosed (n = 64), relapsed (n = 48) and morphologically complete remission (n = 103). The following four features were used to identify immature cCD3+ T cells: CD34+, TdT+, but mCD3-/dim+, and CD45dim+. Among these features, either TdT or CD34 expression was the most useful and were found in 93.8% of patients at diagnosis and 86.7% of patients who relapsed. Although some of the immature markers had disappeared in 23 of 59 cases after therapy, only one case presented with a false negative MRD. Of the 74 consecutive patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT), MRD-positive patients showed a higher relapse rate, a higher cumulative incidence of relapse at 4 years and a shorter median relapse-free survival than MRD-negative patients at post-HSCT(72.7% vs 17.3%, P = 0.000; 100% vs 19.9%, P < 0.0001; and 16 months vs undefined, P < 0.0001). We demonstrated that this panel could be applied to>97% of T-ALL patients to detect MRD and predict relapse after allo-HSCT even in the absence of the initial immunophenotype. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the antibacterial effect of fluoroquinolones (FQs) upon Escherichia coli (E.coli) was measured with and without application of 40kHz ultrasound (US) stimulation. The research results demonstrated that simultaneous application of 40kHz US apparently enhanced the antibacterial effectiveness of FQs. That is, the synergistic effect was observed and the bacterial viability was reduced when FQs and US were combined. In addition, various influencing factors, such as FQs drug concentration, US irradiation time and solution temperature, on the inhibition of E.coli were also investigated. The antibacterial activity was enhanced apparently with increasing of FQs drug concentration, US irradiation time and solution temperature. Furthermore, we discussed preliminarily the mechanism of US enhanced antibacterial activity. Results show that US can activate FQs to produce reactive oxygen species (ROS) indeed, which are mainly determined as superoxide radical anion (·O2 −) and hydroxyl radical (·OH). [Copyright &y& Elsevier]

Abstract: The eight-coordinate (enH2)[YIII(pdta)(H2O)]2·10H2O (en=ethylenediamine and H4pdta=1,3-propylenediamine-N,N,N′,N′-tetraacetic acid) was synthesized, meanwhile its molecular and crystal structures were determined by single-crystal X-ray diffraction technology. The interaction between [YIII(pdta)(H2O)]2 2− and bovine serum albumin (BSA) was investigated by UV–vis and fluorescence spectra. The results indicate that [YIII(pdta)(H2O)]2 2− quenched effectively the intrinsic fluorescence of BSA via a static quenching process with the binding constant (K a) of the order of 104. Meanwhile, the binding and damaging sites to BSA molecules were also estimated by synchronous fluorescence. Results indicate that the hydrophobic environments around Trp and Tyr residues were all slightly changed. The thermodynamic parameters (ΔG =−25.20kJmol−1, ΔH= −26.57kJmol−1 and ΔS= −4.58Jmol−1 K−1) showed that the reaction was spontaneous and exothermic. What is more, both ΔH and ΔS were negative values indicated that hydrogen bond and Van der Waals forces were the predominant intermolecular forces between [YIII(pdta)(H2O)]2 2− and BSA. [ABSTRACT FROM AUTHOR]