Water-Mediated Hydrogen Bond Network Drives Highly Crystalline Structure Formation of Crown Ether-Based Covalent Organic Framework for Sr Adsorption.

Covalent organic frameworks (COFs) with crown ether units have drawn great attention due to their potential applications in adsorption, catalysis, and sensing. However, employing crown ethers to construct COFs is still challenging in light of the flexible nature of macrocycles. Here, a highly crystalline one-dimensional covalent organic framework (1D-18C6-COF) with crown ether units on the ribbon edge was synthesized. The water-mediated hydrogen bond network and π-π stacking hold the 1D COF ribbons together. The combination of experimental and DFT studies demonstrated that the hydrogen bond network plays a crucial role in the structure crystallinity. The 1D-18C6-COF was applied as an adsorbent for strontium, and it exhibited rapid kinetics with good selectivity. In the competitive adsorption experiment, a separation factor of 1900 was achieved, representing one of the largest values for cesium/strontium separation. This work provides new insights into the design and functional exploration of crystalline COFs with flexible units.

Spinal anesthesia for L5-S1 interlaminar endoscopic lumbar discectomy: a retrospective study.

OBJECTIVE: This study aimed to report our experience with spinal anesthesia (SA) in patients undergoing L5-S1 interlaminar endoscopic lumbar discectomy (IELD) and clarify its advantages and disadvantages. METHODS: One hundred twelve patients who underwent IELD for an L5-S1 disc herniation under SA were retrospectively analyzed. SA with 0.5% ropivacaine was administered using a 27-gauge fine needle. Intraoperatively, the volume and level of SA, surgical time, blood loss, and cardiopulmonary complications were documented. Postoperative data was collected included the number of patients who ambulated on the day of surgery, incidence of complications and were then statistically analyzed. RESULTS: Analgesia was complete throughout the entire operation in all patients and no other adjuvant intraoperative analgesic drugs were needed. Mean visual analog scale scores for intraoperative and early postoperative (24 h) pain were 0 and 2.43 ± 1.66. SA was administered at the L3-4 interspace in 34 patients (30.4%) and the L2-3 interspace in 78 (69.6%). Administration was successful with the first attempt in all patients. Mean operation time was 70.12 ± 6.52 min. Mean intraoperative blood loss volume was 20.71 ± 5.26 ml. Ninety-eight patients ambulated on the same day as surgery. Mean length of hospital stay was 24.36 ± 3.64 h. Dural injury without damaging the nerve root occurred in one patient. One patient experienced recurrent disc herniation. Intraoperative hypotension and respiratory distress occurred in five (4.5%) and three (2.7%) patients, respectively. Three patients (2.7%) received postoperative analgesia therapy and two (1.8%) experienced nausea. Two patients (1.8%) developed urinary retention. Spinal headache, cauda equina syndrome, and neurotoxicity did not occur. CONCLUSION: SA can achieve satisfactory pain control for patients undergoing IELD with a low incidence of adverse events. SA may be a useful alternative to local and general anesthesia for IELD surgery. Future randomized controlled trials are warranted to investigate.

Correlation between preoperative frailty and postoperative delirium in elderly patients undergoing hip arthroplasty.

BACKGROUND: Postoperative delirium (POD) refers to acute brain dysfunction occurring within 7 days after operation or before discharge. Frailty refers to the state that the body's physiological reserve is insufficient, so that the compensative capacity to endogenous and exogenous stress stimuli decreases. The purpose of this study is to explore the association of preoperative frailty (PF) with POD in elderly patients undergoing hip arthroplasty. METHODS: Totally 228 elderly patients (age ≥ 65 years) who received elective hip arthroplasty in the Ningbo No. 6 Hospital between December 2021 and June 2022 were enrolled. One day before surgery, the frailty phenotype scale was adopted for evaluation of patients' frailty. On the 1st-3rd day after operation, the confusion assessment method was adopted for evaluation of delirium, and the patients were grouped into a POD group and non-POD group. Logistic regression was conducted to analyze the correlation between PF and POD. RESULTS: Among the patients, the incidence of PF was 30.70% (70/228), and the incidence of delirium within 3 days after operation was 25.88% (59/228). According to binary logistic regression analysis, PF, age, hypertension, diabetes mellitus, and preoperative sleep disorder were independent risk factors for POD in elderly patients undergoing hip arthroplasty (all P < .05). CONCLUSION: PF is a crucial risk factor for POD in elderly patients undergoing hip arthroplasty.

Selective CO2 reduction to CH3OH over atomic dual-metal sites embedded in a metal-organic framework with high-energy radiation.

The efficient use of renewable X/γ-rays or accelerated electrons for chemical transformation of CO2 and water to fuels holds promise for a carbon-neutral economy; however, such processes are challenging to implement and require the assistance of catalysts capable of sensitizing secondary electron scattering and providing active metal sites to bind intermediates. Here we show atomic Cu-Ni dual-metal sites embedded in a metal-organic framework enable efficient and selective CH3OH production (~98%) over multiple irradiated cycles. The usage of practical electron-beam irradiation (200 keV; 40 kGy min-1) with a cost-effective hydroxyl radical scavenger promotes CH3OH production rate to 0.27 mmol g-1 min-1. Moreover, time-resolved experiments with calculations reveal the direct generation of CO2•‒ radical anions via aqueous electrons attachment occurred on nanosecond timescale, and cascade hydrogenation steps. Our study highlights a radiolytic route to produce CH3OH with CO2 feedstock and introduces a desirable atomic structure to improve performance.

Effect of Regional vs General Anesthesia on Incidence of Postoperative Delirium in Older Patients Undergoing Hip Fracture Surgery: The RAGA Randomized Trial.

Importance: In adults undergoing hip fracture surgery, regional anesthesia may reduce postoperative delirium, but there is uncertainty about its effectiveness. Objective: To investigate, in older adults undergoing surgical repair for hip fracture, the effects of regional anesthesia on the incidence of postoperative delirium compared with general anesthesia. Design, Setting, and Participants: A randomized, allocation-concealed, open-label, multicenter clinical trial of 950 patients, aged 65 years and older, with or without preexisting dementia, and a fragility hip fracture requiring surgical repair from 9 university teaching hospitals in Southeastern China. Participants were enrolled between October 2014 and September 2018; 30-day follow-up ended November 2018. Interventions: Patients were randomized to receive either regional anesthesia (spinal, epidural, or both techniques combined with no sedation; n = 476) or general anesthesia (intravenous, inhalational, or combined anesthetic agents; n = 474). Main Outcomes and Measures: Primary outcome was incidence of delirium during the first 7 postoperative days. Secondary outcomes analyzed in this article include delirium severity, duration, and subtype; postoperative pain score; length of hospitalization; 30-day all-cause mortality; and complications. Results: Among 950 randomized patients (mean age, 76.5 years; 247 [26.8%] male), 941 were evaluable for the primary outcome (6 canceled surgery and 3 withdrew consent). Postoperative delirium occurred in 29 (6.2%) in the regional anesthesia group vs 24 (5.1%) in the general anesthesia group (unadjusted risk difference [RD], 1.1%; 95% CI, -1.7% to 3.8%; P = .48; unadjusted relative risk [RR], 1.2 [95% CI, 0.7 to 2.0]; P = .57]). Mean severity score of delirium was 23.0 vs 24.1, respectively (unadjusted difference, -1.1; 95% CI, -4.6 to 3.1). A single delirium episode occurred in 16 (3.4%) vs 10 (2.1%) (unadjusted RD, 1.1%; 95% CI, -1.7% to 3.9%; RR, 1.6 [95% CI, 0.7 to 3.5]). Hypoactive subtype in 11 (37.9%) vs 5 (20.8%) (RD, 11.5; 95% CI, -11.0% to 35.7%; RR, 2.2 [95% CI, 0.8 to 6.3]). Median worst pain score was 0 (IQR, 0 to 20) vs 0 (IQR, 0 to 10) (difference 0; 95% CI, 0 to 0). Median length of hospitalization was 7 days (IQR, 5 to 10) vs 7 days (IQR, 6 to 10) (difference 0; 95% CI, 0 to 0). Death occurred in 8 (1.7%) vs 4 (0.9%) (unadjusted RD, -0.8%; 95% CI, -2.2% to 0.7%; RR, 2.0 [95% CI, 0.6 to 6.5]). Adverse events were reported in 106 episodes in the regional anesthesia group and 102 in the general anesthesia group; the most frequently reported adverse events were nausea and vomiting (47 [44.3%] vs 34 [33.3%]) and postoperative hypotension (13 [12.3%] vs 10 [9.8%]). Conclusions and Relevance: In patients aged 65 years and older undergoing hip fracture surgery, regional anesthesia without sedation did not significantly reduce the incidence of postoperative delirium compared with general anesthesia. Trial Registration: ClinicalTrials.gov Identifier: NCT02213380.

Thorium(IV) adsorption onto multilayered Ti3C2Tx MXene: a batch, X-ray diffraction and EXAFS combined study.

The interlayer regulation of layered environmental adsorption materials such as two-dimensional early transition metal carbides and carbonitrides (MXenes) plays an important role in their purification performance for specific pollutants. Here the enhanced uptake of ThIV by multilayered titanium carbides (Ti3C2Tx) through a hydrated intercalation strategy is reported. ThIV adsorption behaviors of three Ti3C2Tx samples with different c lattice parameters were studied as a function of contact time, pH, initial concentration, temperature and ion strength in batch experiments. The results indicated that the ThIV uptake was pH and ionic strength dependent, and the adsorption process followed the pseudo-second-order kinetics and the heterogeneous isotherm (Freundlich) model. Thermodynamic data suggested that the adsorption process of all MXene samples was a spontaneous endothermic reaction. The dimethyl sulfoxide intercalated hydrated Ti3C2Tx featured the largest interlayer space and exhibited the highest ThIV adsorption capacity (162 mg g-1 at pH 3.4 or 112 mg g-1 at pH 3.0), reflecting the significant increase in available adsorption sites from Ti3C2Tx interlayers. The adsorption mechanism has been clarified based on adsorption experiments and spectroscopic characterizations. An ion exchange process was proposed for the interaction between hydrated MXenes and ThIV, where H+ from surface [Ti-O]-H+ groups were the primary active sites on Ti3C2Tx. Extended X-ray absorption fine structure (EXAFS) fitting results, in combination with X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses, clearly indicated that ThIV mainly formed the outer-sphere complexes on Ti3C2Tx surface through electrostatic interaction under strong acid conditions, while at pH > 3.0 the adsorption mechanism was determined by inner-sphere coordination and electrostatic interaction together.

In-situ anodic precipitation process for highly efficient separation of aluminum alloys.

Electrorefining process has been widely used to separate and purify metals, but it is limited by deposition potential of the metal itself. Here we report in-situ anodic precipitation (IAP), a modified electrorefining process, to purify aluminium from contaminants that are more reactive. During IAP, the target metals that are more cathodic than aluminium are oxidized at the anode and forced to precipitate out in a low oxidation state. This strategy is fundamentally based on different solubilities of target metal chlorides in the NaAlCl4 molten salt rather than deposition potential of metals. The results suggest that IAP is able to efficiently and simply separate components of aluminum alloys with fast kinetics and high recovery yields, and it is also a valuable synthetic approach for metal chlorides in low oxidation states.

Triptolide Attenuates Neuropathic Pain by Regulating Microglia Polarization through the CCL2/CCR2 Axis.

Triptolide (T10) is a common anti-inflammatory and analgesic drug. However, the activation of microglia and elimination of the corresponding inflammatory response are new targets for the treatment of neuropathic pain. Chemokine CCL (CCL2) is a key mediator for activating microglia. In this study, the effects of triptolide on the activation and polarization of microglia cells and CCL2 and its corresponding receptor, chemokine receptor 2 (CCR2), were mainly discussed. Microglia were stimulated with 1 µg/mL lipopolysaccharide (LPS) and pretreated with 10, 20, and 40 nM T10 and CCR2 antagonist (RS102895), respectively. The quantitative polymerase chain reaction (QPCR) and western blot results showed that T10 could obviously inhibit the upregulation of CCL2 and CCR2 induced by LPS stimulation in microglia cells, inhibit the fluorescence intensity of glial fibrillary acidic protein (GFAP) and inducible nitric oxide synthase (iNOS) antibody immunostaining in cells, and upregulate the fluorescence intensity of arginase 1 antibody in cells. The expression of interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α) was inhibited in a dose-dependent manner. RS102895 can significantly reverse the activation and M2 polarization of microglia pretreated with 40 nM T10 and weaken the anti-inflammatory effect of T10. The addition of CCL2 did not extremely affect the function of RS102895. T10 may inhibit microglia activation and M1 polarization by inhibiting the expression of CCL2 and CCR2, promoting M2 polarization, reducing the level of inflammatory factors in cells, and exerting its analgesic effect, which is worthy of clinical promotion as a drug for neuropathic pain.

Highly efficient adsorption and immobilization of U(VI) from aqueous solution by alkalized MXene-supported nanoscale zero-valent iron.

A novel composite of zero-valent iron nanoparticles supported on alkalized Ti3C2Tx nanoflakes (nZVI/Alk-Ti3C2Tx) was constructed by an in-situ growth method for simultaneous adsorption and reduction U(VI) from aqueous solution in anoxic conditions. The effect of various factors such as adsorbent dose, pH, ionic strength, contact time, initial U(VI) concentration and environmental media were comprehensively investigated by batch experiments. Benefiting from the good dispersion uniformity of nZVI on MXene substrates, nZVI/Alk-Ti3C2Tx exhibited rapid removal kinetics, excellent selectivity, 100% removal efficiency and up to 1315 mg g-1 uptake capacity for U(VI) capture. In the presence of mimic groundwater, 1.0 mM NaHCO3 and 10 mg L-1 humic acid, the removal percentages of U(VI) by the composites could reach 95.1%, 88.9% and 69.5%, respectively. The reaction mechanism between U(VI) and nZVI/Alk-Ti3C2Tx has been clarified based on FTIR, XANES, XPS and XRD analysis. Depending on the consumption of reactive nZVI in the composites and the solution pH, the elimination of U(VI) could be realized by different pathways including reductive immobilization in the form of UO2, inner-sphere surface complexation and hydrolysis precipitation. The present study illustrates that the nZVI/Alk-Ti3C2Tx composite may be an efficient scavenger for radioactive wastewater purification in environmental remediation.

Actinide Separation Inspired by Self-Assembled Metal-Polyphenolic Nanocages.

The separation of actinides has a vital place in nuclear fuel reprocessing, recovery of radionuclides, and remediation of environmental contamination. Here we propose a new paradigm of nanocluster-based actinide separation, namely, nanoextraction, that can achieve efficient sequestration of uranium in an unprecedented form of giant coordination nanocages using a cone-shaped macrocyclic pyrogallol[4]arene as the extractant. The U24-based hexameric pyrogallol[4]arene nanocages with distinctive [U2(PG)2] binuclear units (PG = pyrogallol) that rapidly assembled in situ in monophasic solvent were identified by single-crystal X-ray diffraction, MALDI-TOF mass spectrometry, NMR spectroscopy, and small-angle X-ray and neutron scattering. Comprehensive biphasic extraction studies showed that this novel separation strategy has enticing advantages such as fast kinetics, high efficiency, and good selectivity over lanthanides, thereby demonstrating its potential for efficient separation of actinide ions.

Knockdown of lncRNA PCAI protects against cognitive decline induced by hippocampal neuroinflammation via regulating SUZ12.

AIMS: Postoperative cognitive dysfunction (POCD) is a common postoperative complication that is associated with increased morbidity and mortality. However, the mechanism of pathogenesis of POCD still remains largely unknown. The aim of the study was to investigate the function and mechanism of lncRNA PCAI in POCD. MATERIALS AND METHODS: Knockdown and overexpression studies were performed to analyze the function of lncRNA PCAI in cultured BV-2 cell lines treated with LPS to mimic the neuroinflammation. Real-time PCR, western blot, ELISA were used to determine the expression level of inflammation markers. Rescue experiment was performed to prove the relationship between PCAI and SUZ12. RESULTS: We found that the expression of lncRNA PCAI was decreased with the increasing concentrations of LPS. Knockdown of lncRNA PCAI inhibited the cell death rates and attenuated the cell inflammation via ELISA and real-time PCR. Besides, downregulated of lncRNA PCAI can protect the mitochondrial function via membrane potential assay. Overexpression of lncRNA PCAI can promote the cell death and inflammation response induced by LPS. We also provided mechanism study about lncRNA PCAI that negatively regulating SUZ12. Rescue experiment also verified the results. CONCLUSION: We performed comprehensive study of functional analysis of lncRNA PCAI in POCD and proved its mechanism, which negatively regulate SUZ12. Our study provided new clues for the clinical intervention and targets for POCD.

Oxyntomodulin attenuates TNF­α induced neuropathic pain by inhibiting the activation of the NF­κB pathway.

Neuropathic pain is rarely diagnosed. Oxyntomodulin is peripherally and centrally distributed; however, the potential mechanisms underlying the effects of oxyntomodulin in attenuating nociception remain unclear; thus, we aimed to explore them in the present study. A neuropathic pain model in male C57BL/6 mice was induced by intrathecal injection of tumor necrosis factor­α (TNF­α), and the duration of nociceptive behavioral responses was measured with a stop­watch timer within 30 min. Western blotting was used to explore the protein levels of ionized calcium binding adaptor molecule­1 (IBA1), nuclear factor­κB (NF­κB) phosphorylated­p65, interleukin (IL)­6 and IL­1ß. We performed reverse transcription­quantitative polymerase chain reaction and ELISA were performed to determine the mRNA and protein expression levels of IL­6 and IL­1ß, respectively. An MTT assay was conducted to detect BV2 cell viability. Oxyntomodulin was observed to attenuate TNF­α­induced pain hypersensitivity in mice, as well as the expression of IBA1, NF­κB p­p65, IL­6 and IL­1ß in the spinal cord. Oxyntomodulin exhibited no cytotoxicity on BV2 cells, and attenuated TNF­α­induced IL­6 and IL­1ß production and release in BV2 cells and culture medium, respectively. Collectively, we proposed oxyntomodulin to attenuate TNF­α induced neuropathic pain associated with the release of glial cytokines IL­6 and IL­1ß via inhibiting the activation of the NF­κB pathway.

Sequence Analysis and Comparison of the Key Genes of Domestic Live Attenuated Varicella Vaccine.

Objective To analyze the safety and consistency of domestic live attenuated varicella vaccines (LAVVs) at gene level.Methods The key genes (ORF38,ORF54,and ORF62) of LAVVs produced by four Chinese manufacturers were amplified by polymerase chain reaction (PCR) and sequenced.The sequencing results were compared with the sequences of Dumas,P-Oka,and V-Oka strains in GenBank and with the sequences of Varilrix (GSK) and Varivax (Merck).Results The ORF38 and ORF54 gene sequences of four domestic LAVVs were the same as each other and completely consistent with the sequences of V-Oka and Varilrix;however,it was different from Varivax (Merck) at one site.The ORF62 gene sequences of four domestic LAVVs were similar,and had individual nucleotide differences with V-Oka,Varilrix(GSK),and Varivax (Merck).Conclusions The sequences of ORF38,ORF54,and ORF62 of four domestic LAVVs are almost the same,showing good stability.They have small differences with V-Oka,Varilrix(GSK),and Varivax (Merck),without introducing new mutations.

Efficient removal of uranium from aqueous solution by zero-valent iron nanoparticle and its graphene composite.

Zero-valent iron nanoparticle (ZVI-np) and its graphene composites were prepared and applied in the removal of uranium under anoxic conditions. It was found that solutions containing 24 ppm U(VI) could be completely cleaned up by ZVI-nps, regardless of the presence of NaHCO3, humic acid, mimic groundwater constituents or the change of solution pH from 5 to 9, manifesting the promising potential of this reactive material in permeable reactive barrier (PRB) to remediate uranium-contaminated groundwater. In the measurement of maximum sorption capacity, removal efficiency of uranium kept at 100% until C0(U) = 643 ppm, and the saturation sorption of 8173 mg U/g ZVI-nps was achieved at C0(U) = 714 ppm. In addition, reaction mechanisms were clarified based on the results of SEM, XRD, XANES, and chemical leaching in (NH4)2CO3 solution. Partially reductive precipitation of U(VI) as U3O7 was prevalent when sufficient iron was available; nevertheless, hydrolysis precipitation of U(VI) on surface would be predominant as iron got insufficient, characterized by releases of Fe(2+) ions. The dissolution of Fe(0) cores was assigned to be the driving force of continuous formation of U(VI) (hydr)oxide. The incorporation of graphene supporting matrix was found to facilitate faster removal rate and higher U(VI) reduction ratio, thus benefitting the long-term immobilization of uranium in geochemical environment.

Exploring actinide materials through synchrotron radiation techniques.

Synchrotron radiation (SR) based techniques have been utilized with increasing frequency in the past decade to explore the brilliant and challenging sciences of actinide-based materials. This trend is partially driven by the basic needs for multi-scale actinide speciation and bonding information and also the realistic needs for nuclear energy research. In this review, recent research progresses on actinide related materials by means of various SR techniques were selectively highlighted and summarized, with the emphasis on X-ray absorption spectroscopy, X-ray diffraction and scattering spectroscopy, which are powerful tools to characterize actinide materials. In addition, advanced SR techniques for exploring future advanced nuclear fuel cycles dealing with actinides are illustrated as well.

Introduction of bifunctional groups into mesoporous silica for enhancing uptake of thorium(IV) from aqueous solution.

The potential industrial application of thorium (Th), as well as the environmental and human healthy problems caused by thorium, promotes the development of reliable methods for the separation and removal of Th(IV) from environmental and geological samples. Herein, the phosphonate-amino bifunctionalized mesoporous silica (PAMS) was fabricated by a one-step self-assembly approach for enhancing Th(IV) uptake from aqueous solution. The synthesized sorbent was found to possess ordered mesoporous structures with uniform pore diameter and large surface area, characterized by SEM, XRD, and N2 sorption/desorption measurements. The enhancement of Th(IV) uptake by PAMS was achieved by coupling of an access mechanism to a complexation mechanism, and the sorption can be optimized by adjusting the coverage of the functional groups in the PAMS sorbent. The systemic study on Th(IV) sorption/desorption by using one coverage of PAMS (PAMS12) shows that the Th(IV) sorption by PAMS is fast with equilibrium time of less than 1 h, and the sorption capacity is more than 160 mg/g at a relatively low pH. The sorption isotherm has been successfully modeled by the Langmuir isotherm and D-R isotherm, which reveals a monolayer homogeneous chemisorption of Th(IV) in PAMS. The Th(IV) sorption by PAMS is pH dependent but ionic strength independent. In addition, the sorbed Th(IV) can be completely desorbed using 0.2 mol/L or more concentrated nitric acid solution. The sorption test performed in the solution containing a range of competing metal ions suggests that the PAMS sorbent has a desirable selectivity for Th(IV) ions.

Efficient removal of caesium ions from aqueous solution using a calix crown ether in ionic liquids: mechanism and radiation effect.

The removal of radioactive (137)Cs from nuclear waste is of great importance for both the environment and energy saving. Herein, we report a study on the removal of Cs(+) using a calix crown ether bis(2-propyloxy)calix[4]crown-6 (BPC6) in ionic liquids [C(n)mim][NTf(2)], where [C(n)mim](+) is 1-alkyl-3-methylimidazolium and [NTf(2)](-) is bis(trifluoromethylsulfonyl)imide. The BPC6/[C(n)mim][NTf(2)] system is highly efficient in removing Cs(+) from aqueous solution, even at a low concentration of BPC6. HNO(3) and metal ions such as Na(+), Al(3+) in the aqueous phase interfered with the extraction of Cs(+) by competitive interaction with BPC6 and/or salting-out effect. UV analysis confirmed that the extraction of Cs(+) by the BPC6/[C(n)mim][NTf(2)] system involves a dual extraction mechanism, i.e., via exchange of BPC6.Cs(+) complex or Cs(+) by [C(n)mim](+). Irradiation of [C(4)mim][NTf(2)] dramatically decreases Cs(+) partitioning in the ionic liquid phase by the competitive interaction of radiation-generated H(+) with BPC6, while irradiation of BPC6/[C(4)mim][NTf(2)] decreases Cs(+) partitioning more markedly due to the radiolysis of BPC6.

Radiation effects on hydrophobic ionic liquid [C4mim][NTf2] during extraction of strontium ions.

The applications of room-temperature ionic liquids (RTILs) in separation of high level radioactive nuclides demand a comprehensive knowledge of the stability and metal ion extraction of RTILs under radiation. Herein, we assessed the influence of gamma-irradiation on the [C(4)mim][NTf(2)]-based extraction system, where [C(4)mim](+) is 1-butyl-3-methylimidazolium and [NTf(2)](-) is bis(trifluoromethylsulfonyl)imide, by solvent extraction of Sr(2+) using irradiated [C(4)mim][NTf(2)] in combination with dicyclohexyl-18-crown-6 (DCH18C6). It was found that the degree of extraction for Sr(2+) from water to irradiated [C(4)mim][NTf(2)] decreased compared with that to unirradiated [C(4)mim][NTf(2)], and the decrement enhanced obviously with increasing dose. NMR spectroscopic probe analysis revealed the formation of acids during irradiation of [C(4)mim][NTf(2)]. The decrease of Sr(2+) partitioning in irradiated [C(4)mim][NTf(2)] is attributed to the competition between H(+) with Sr(2+) to interact with DCH18C6. Accordingly, washing irradiated [C(4)mim][NTf(2)] with water gives a simple way of ionic liquid recycling. Furthermore, the degree of extraction for Sr(2+) from 3 mol.L(-1) nitric acid solution to [C(4)mim][NTf(2)] is independent of the irradiation of [C(4)mim][NTf(2)] since the amount of the radiation-generated H(+) is negligible in such a high acidic solution.

Influence of gamma-radiation on the ionic liquid [C4mim][PF6] during extraction of strontium ions.

The preliminary results presented here show that gamma-irradiation of ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([C4mim][PF6]) markedly decreases Sr2+ partitioning in the crown ether/[C4mim][PF6] extraction phase due to the competition between radiation-generated H+ and Sr2+ to interact with the crown ether, however, washing irradiated [C4mim][PF6] with water gives a simple way of recycling the ionic liquid.

Intramuscular electroporation of a plasmid encoding human plasminogen kringle 5 induces growth inhibition of Lewis lung carcinoma in mice.

Tumor growth and metastasis depend critically on blood vessel formation. Antiangiogenesis, therefore, represents a promising strategy for cancer therapy. The kringle 5 (K5) domain of human plasminogen is a potent angiogenesis inhibitor. To investigate whether intramuscular electroporation (EP) of K5 has antitumor activity in mouse tumor models, we constructed a plasmid encoding K5 (pVAX1-K5). Hela cells transfected with this plasmid produced and secreted K5 that inhibited the migration of human microvascular endothelial cells. Intramuscular EP treatment of pVAX1-K5 inhibited the growth of Lewis lung carcinoma and prolonged the survival time of tumor-bearing mice. Angiogenesis was obviously inhibited, and apoptosis was induced in tumor cells of mice that received intramuscular EP of pVAX1-K5. On the contrary, intramuscular injection of pVAX1-K5 without EP failed to show the same effects. The data indicate that intramuscular EP of plasmid DNA encoding the K5 domain is an effective strategy for the experimental treatment of cancer by expressing K5.