Organophosphorus mineralizing-Streptomyces species underpins uranate immobilization and phosphorus availability in uranium tailings.

Phosphate-solubilizing bacteria (PSB) are important but often overlooked regulators of uranium (U) cycling in soil. However, the impact of PSB on uranate fixation coupled with the decomposition of recalcitrant phosphorus (P) in mining land remains poorly understood. Here, we combined gene amplicon sequencing, metagenome and metatranscriptome sequencing analysis and strain isolation to explore the effects of PSB on the stabilization of uranate and P availability in U mining areas. We found that the content of available phosphorus (AP), carbonate-U and Fe-Mn-U oxides in tailings was significantly (P < 0.05) higher than their adjacent soils. Also, organic phosphate mineralizing (PhoD) bacteria (e.g., Streptomyces) and inorganic phosphate solubilizing (gcd) bacteria (e.g., Rhodococcus) were enriched in tailings and soils, but only organic phosphate mineralizing-bacteria substantially contributed to the AP. Notably, most genes involved in organophosphorus mineralization and uranate resistance were widely present in tailings rather than soil. Comparative genomics analyses supported that organophosphorus mineralizing-Streptomyces species could increase soil AP content and immobilize U(VI) through organophosphorus mineralization (e.g., PhoD, ugpBAEC) and U resistance related genes (e.g., petA). We further demonstrated that the isolated Streptomyces sp. PSBY1 could enhance the U(VI) immobilization mediated by the NADH-dependent ubiquinol-cytochrome c reductase (petA) through decomposing organophosphorous compounds. This study advances our understanding of the roles of PSB in regulating the fixation of uranate and P availability in U tailings.

Coherent Modulation of the Aggregation Behavior and Intramolecular Charge Transfer in Small Molecule Probes for Sensitive and Long-term Nerve Agent Monitoring.

Aggregation-induced emission (AIE) shows promising performance in chemical sensing relying on the change of the emission behavior of the probe molecule monomers to the aggregated product. However, whether the response contrast could be further boosted by utilizing the emission property of the aggregated probe and the aggregated product remains a big challenge. Here, an exciting AIE probe regulation strategy was proposed by coherently modulating the aggregation behavior and the intramolecular charge transfer (ICT) property of the probes and thus an aggregated-to-aggregated colorimetric-fluorescent dual-mode detection was achieved. The blue emissive film obtained with the optimal AIE probe has been proven to be effective to recognize the vapor of nerve agent analog DCP in air by emitting a sharp green fluorescence. In addition, a porous polymer-based wet sensing chip loaded with the probe enables the immediate response to DCP vapor with a limit of detection (LOD) of 1.7 ppb, and it was further integrated into a wearable watch device for long-term monitoring of DCP vapor up to two weeks. We expect the present probe design strategy would greatly deepen the AIE-based science and provide new insights for long-term monitoring sensors toward trace hazardous substances.

Clinical efficacy of sufentanil combined with dexmedetomidine in patient-controlled subcutaneous analgesia for advanced cancer pain.

To evaluate the efficacy of sufentanil combined with dexmedetomidine in patient-controlled subcutaneous analgesia (PSCA) for advanced cancer pain, 62 patients with advanced cancer pain treated in Department of Oncology of Hebei PetroChina Central Hospital from January 2017 to May 2020 were recruited and assigned via the random number table method to either the control group or the observation group. The control group (group A) received PSCA with sufentanil and the observation group was divided into group B1 receiving PSCA with sufentanil and dexmedetomidine (20:1) and group B2 given PSCA with sufentanil and dexmedetomidine (10:1). The numeric rating scale (NRS) scores of patients in the three groups decreased significantly after medication (P<0.05), with significantly lower NRS scores in groups B1 and B2 than in group A (P<0.05) and comparable results between groups B1 and B2 (P>0.05). Significantly higher Ramsay sedation scores were observed in groups B1 and B2 than in group A after drug administration (P<0.05), without significant differences between groups B1 and B2 (P>0.05). The incidence of constipation, nausea and vomiting in group B1 and group B2 was significantly lower than that in group A. PSCA with sufentanil and dexmedetomidine is effective in patients with cancer pain.

Amorphous Copper-Based Nanoparticles with Clusterization-Triggered Phosphorescence for Ultrasensing 2,4,6-Trinitrotoluene.

Amorphous metal-based nanostructures have attracted great attention recently due to their facilitative electron transfer and abundant reactive sites, whereas it remains enigmatic as to whether amorphous copper-based nanoparticles (CuNPs) can be achieved. Here, for synthesizing amorphous CuNPs, glutathione is adopted as a ligand to inhibit the nucleation and crystallization process via its electrostatic repulsion. By subtly tailoring the solvent polarity, not only can amorphous glutathione-functionalized CuNPs (GSH-CuNPs) with phosphorescent performance be achieved after transferring the non-conjugation of GSH ligand to through-space conjugation, namely clusterization-triggered emission, but also the phosphorescence-off of GSH-CuNPs toward 2,4,6-trinitrotoluene (TNT) can be realized by the photoinduced electron-transfer process through the hydrogen bond channel, which is established between carboxyl and amino groups of GSH-CuNPs with the nitryl group of TNT. Benefitting from the intrinsic superiorities of the amorphous CuNPs, desired phosphorescence and detection performances of GSH-CuNPs toward airborne TNT microparticulates are undoubtedly realized, including high quantum yield (13.22%), excellent specificity in 33 potential interferents, instantaneous response, and ultralow detection limit (1.56 pg). The present GSH-CuNPs are expected to stretch amorphous metal-based nanostructures and deepen the insights into amorphous materials for optical detection.

Polyethyleneimine-capped copper nanoclusters for detection and discrimination of 2,4,6-trinitrotoluene and 2,4,6-trinitrophenol.

The detection and discrimination of 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (TNP) from analogues are of great importance to global security and are full of challenges in the field of trace sensing. Here, benefitting from the strong electrophilicity of TNT, a sensing strategy is established by synthesizing polyethyleneimine capped copper nanoclusters (PEI-Cu NCs) with abundant -NH2 groups. By carefully controlling the size and structure of PEI-Cu NCs, Förster resonance energy transfer (FRET) from PEI-Cu NCs to the Meisenheimer complex occurs resulting from their spectral overlap when detecting TNT, while, due to the energy level match of TNP with PEI-Cu NCs, as well as the strong affinity between its -OH and -NH2 in PEI-Cu NCs, photo-induced electron transfer (PET) is feasibly expected. As a result, TNT and TNP could be detected from 26 types of analogues and cations with a limit of detection (LOD) of 26.57 and 12.82 nM, respectively. Besides, owing to the brown color of the Meisenheimer complex, the discrimination of TNT and TNP could be additionally realized by colorimetric detection. We expect that the proposed methodology would not only shine light on the detection and discrimination of TNT and TNP that mitigate against public security concerns, but also pave a way for the deep understanding of FRET and PET related fluorescence quenching mechanisms from the aspect of controllable sensing material design and synthesis.

Removal of heavy metals from aqueous solution using chitosan-combined magnetic biochars.

The use of chitosan combined with magnetic Loofah biochar (CMLB) was investigated for the removal of Cr(VI) and Cu(II) from aqueous solution. The modified biochar had higher Cr(VI) and Cu(II) adsorption capacity than that of pristine biochar. 40%-CMLB showed high Cr(VI) and Cu(II) adsorption capacity of 30.14 mg/g, and 54.68 mg/g, respectively. Adsorption reached equilibrium within 18 h. The study found that the experimental data showed the best fit for the pseudo-second-order kinetic model and Freundlich model. Additionally, after three reuse cycles, Cr(VI) and Cu(II) adsorption capacity by CMLB were 23.34 mg/g and 42.6 mg/g, respectively. XPS results indicated that ion exchange and surface complexation were the primary mechanisms for Cr(VI) and Cu(II) adsorption.

Enhancing 2-Ketogluconate Production of Pseudomonas plecoglossicida JUIM01 by Maintaining the Carbon Catabolite Repression of 2-Ketogluconate Metabolism.

2-Ketogluconate (2KGA) is an organic acid that is important for pharmaceutical, cosmetic, and environmental applications. Pseudomonas plecoglossicida JUIM01 strain is an important industrial 2KGA producer in China. In this paper, we found that P. plecoglossicida JUIM01 could convert glucose to 2KGA extracellularly, and the formed 2KGA was subsequently consumed after glucose was exhausted during the fermentation process. Experiments of glucose and 2KGA supplementation during fermentation process revealed that, only when glucose was exhausted, the strain started to consume the product 2KGA. Then, the mechanism of this phenomenon was investigated at transcription and protein levels, and the results indicated that P. plecoglossicida JUIM01 possesses carbon catabolite repression of 2KGA metabolism by glucose. Next, increasing the supply of glucose could attenuate 2KGA consumption and enhance the 2KGA yield from glucose. Finally, fed-batch fermentation of P. plecoglossicida JUIM01 resulted in 205.67 g/L of 2KGA with a productivity of 6.86 g/L/h and yield of 0.953 g/g glucose. These results can provide references for the industrial fermentation production of 2KGA and other fermentation products.

[Abnormality of blood coagulation indexes in patients with de novo acute leukemia and its clinical significance].

To explore hemorrhage risk and the clinical significance of abnormal change of prothrombin time (PT), activated partial thromboplastin time (APTT), plasma fibrinogen (FIB), plasma thrombin time (TT) and d-dimer (D-D) in de novo acute leukemia (except for APL), the different bleeding manifestations of 114 cases of de novo acute leukemia with different coagulation indexes were analyzed retrospectively. The correlation between these blood coagulation indexes and the possible correlative clinical characteristics were analysed, including age, sex, type of acute leukemia, initial white blood cell(WBC) and platelet(Plt) count, the proportion of blast cells in bone marrow and cytogenetic abnormality of patients at diagnosis. The results indicated that the incidence of abnormal blood coagulation was as high as 78.1% for de novo AL patients. These patients with 5 normal blood coagulation indexes may have mild bleeding manifestation, but the more abnormal indexes, the more severe bleeding. Both PT and D-D were sensitive indexes for diagnosis of level II bleeding. Incidence of abnormal blood coagulation significantly correlates with the proportion of blast cells in bone marrow (χ(2) = 4.184, OR = 1.021, P < 0.05) and more with D-D (P < 0.01), while age, sex, type of AL, WBC count, Plt count and abnormality of cytogenetics did not correlate with abnormal blood coagulation. It is concluded that the coagulation and fibrinolysis are abnormal in most patients with de novo acute leukemia. More abnormal indexes indicate more severe bleeding, and both PT and D-D are sensitive indexes for diagnosis of level II bleeding. Higher proportion of blast cells in bone marrow predicts higher incidence of abnormal blood clotting. Acute leukemia with elderly age, high white blood cell count and adverse cytogenetics do not predict severer abnormal blood clotting. Detection of PT, APTT, TT, FIB, and D-D may help to judge whether the patients are in a state of hypercoagulability or disseminated intravenous coagulation, which will provide experiment evidences for early intervention and medication.

[Effect of the proteasome inhibitor MG-132 on hyperoxic lung injury and its mechanism in rats].

OBJECTIVE: To observe the effects of proteasome inhibitor MG-132 on hyperoxic lung injury in rats and explore the mechanism. METHODS: Thirty SD rats were randomly divided into 3 groups, namely the normoxic group, hyperoxic group, and hyperoxic with MG-132 treatment group, and rat models of hyperoxic exposure-induced lung injury were established in the latter two groups. After pathological grading of the lung injury under optical microscope and determination of the wet/dry weight ratio of the lung tissue, the expressions of ubiquitin protein and nuclear factor-kappaB (NF-kappaB) p56 and the activity of proteasome 20S and myeloperoxidase (MPO) were detected. Tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) expressions in the lung tissue were also detected. RESULTS: The rats with hyperoxic exposure showed obvious pulmonary edema and increased wet/dry weight ratio of the lung tissue (P<0.01), which were significantly alleviated with MG-132 treatment (P<0.01). Compared with the normoxic group, hyperoxic exposure resulted in significant lung pathologies (P<0.01), which was reduced after MG-132 treatment. Immunohistochemistry and Western blotting demonstrated increased expression of ubiquitin protein in the lung tissue after hyperoxic exposure (P<0.01), which was lowered by MG-132 treatment (P<0.01). Proteasome 20S activity was obviously enhanced in the hyperoxic group (P<0.01) but lowered by MG-132 treatment (P<0.01). Hyperoxic exposure also caused obviously enhanced MPO activity and expressions of NF-kappaB, TNF-alpha, and IL-6 (P<0.01), which were all reduced by MG-132 treatment (P<0.05). CONCLUSION: MG-132 alleviates hyperoxic lung injury probably by inhibiting the NF-kappaB/inflammatory factor pathways.