The Liquid Jet Endstation for Hard X-ray Scattering and Spectroscopy at the Linac Coherent Light Source.

The ability to study chemical dynamics on ultrafast timescales has greatly advanced with the introduction of X-ray free electron lasers (XFELs) providing short pulses of intense X-rays tailored to probe atomic structure and electronic configuration. Fully exploiting the full potential of XFELs requires specialized experimental endstations along with the development of techniques and methods to successfully carry out experiments. The liquid jet endstation (LJE) at the Linac Coherent Light Source (LCLS) has been developed to study photochemistry and biochemistry in solution systems using a combination of X-ray solution scattering (XSS), X-ray absorption spectroscopy (XAS), and X-ray emission spectroscopy (XES). The pump-probe setup utilizes an optical laser to excite the sample, which is subsequently probed by a hard X-ray pulse to resolve structural and electronic dynamics at their intrinsic femtosecond timescales. The LJE ensures reliable sample delivery to the X-ray interaction point via various liquid jets, enabling rapid replenishment of thin samples with millimolar concentrations and low sample volumes at the 120 Hz repetition rate of the LCLS beam. This paper provides a detailed description of the LJE design and of the techniques it enables, with an emphasis on the diagnostics required for real-time monitoring of the liquid jet and on the spatiotemporal overlap methods used to optimize the signal. Additionally, various scientific examples are discussed, highlighting the versatility of the LJE.

Oral Administration of Euonymus alatus Leaf Extract Ameliorates Alzheimer's Disease Phenotypes in 5xFAD Transgenic Mice.

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease and is frequently characterized by progressive and irreversible impairment of cognitive functions. However, its etiology remains poorly understood, limiting therapeutic interventions. Our previous study showed that the ethanol extract of Euonymus alatus leaves (EA) positively affected scopolamine-induced hypomnesia in the normal mouse model by promoting nuclear factor E2-related factor 2 (Nrf2) activation. Herein, we examined whether EA administration could ameliorate major AD phenotypes that are manifested in 5xFAD transgenic mice. Two-month-old mice were orally administered with EA at a dose of 50, 100, or 150 mg/kg body weight/day thrice a week for 14 weeks. We observed that EA administration improved behavioral deficits as assessed by the passive avoidance, Morris water maze, and Y-maze tasks; decreased the plasma levels of pro-inflammatory cytokines, including TNFα and IL-1ß; decreased the protein expression levels of inflammatory mediators in the hippocampus; and attenuated histological damage and amyloid beta plaques in the hippocampal region of 5xFAD mouse brain. Interestingly, our data demonstrated that the effectiveness was partially attributed to quercetin, which was noted to be a component of EA. Hence, these findings suggest that a long-term administration of EA could alleviate AD symptoms and delay its progression.

Unraveling Metal-Ligand Bonding in an HNO-Evolving {FeNO}6 Complex with a Combined X-ray Spectroscopic Approach.

Photolytic delivery of nitric oxide and nitroxide has substantial biomedical and phototherapeutic applications. Here, we utilized hard X-ray spectroscopic methods to identify key geometric and electronic structural features of two photolabile {FeNO}6 complexes where the compounds differ in the presence of a pendant thiol in [Fe(NO)(TMSPS2)(TMSPS2H)] and thioether in [Fe(NO)(TMSPS2)(TMSPS2CH3)] with the former complex being the only transition metal system to photolytically generate HNO. Fe Kß XES identifies the photoreactant systems as essentially Fe(II)-NO+, while valence-to-core XES extracts a NO oxidation state of +0.5. Finally, the pre-edge of the Fe high-energy-resolution fluorescence detected (HERFD) XAS spectra is shown to be acutely sensitive to perturbation of the Fe-NO covalency enhanced by the 3d-4p orbital mixing dipole intensity contribution. Collectively, this X-ray spectroscopic approach enables future time-resolved insights in these systems and extensions to other challenging redox noninnocent {FeNO}x systems.

Biohybrid CO2 electrolysis for the direct synthesis of polyesters from CO2.

Converting anthropogenic CO2 to value-added products using renewable energy has received much attention to achieve a sustainable carbon cycle. CO2 electrolysis has been extensively investigated, but the products have been limited to some C1-3 products. Here, we report the integration of CO2 electrolysis with microbial fermentation to directly produce poly-3-hydroxybutyrate (PHB), a microbial polyester, from gaseous CO2 on a gram scale. This biohybrid system comprises electrochemical conversion of CO2 to formate on Sn catalysts deposited on a gas diffusion electrode (GDE) and subsequent conversion of formate to PHB by Cupriavidus necator cells in a fermenter. The electrolyzer and the electrolyte solution were optimized for this biohybrid system. In particular, the electrolyte solution containing formate was continuously circulated through both the CO2 electrolyzer and the fermenter, resulting in the efficient accumulation of PHB in C. necator cells, reaching a PHB content of 83% of dry cell weight and producing 1.38 g PHB using 4 cm2 Sn GDE. This biohybrid system was further modified to enable continuous PHB production operated at a steady state by adding fresh cells and removing PHB. The strategies employed for developing this biohybrid system will be useful for establishing other biohybrid systems producing chemicals and materials directly from gaseous CO2.

Electrodeposited Sn-Cu@Sn dendrites for selective electrochemical CO2 reduction to formic acid.

Large-scale CO2 electrolysis can be applied to store renewable energy in chemicals. Recent developments in gas diffusion electrodes now enable a commercially relevant current density. However, the low selectivity of the CO2 reduction reaction (CO2RR) still hinders practical applications. The selectivity of the CO2RR highly depends on the electrocatalyst. Sn catalysts are considered promising cathode materials for the production of formic acid. The selectivity of Sn catalysts can be regulated by controlling their morphology or alloying them with secondary metals. Herein, we enhanced the selectivity of CO2 reduction to formic acid by synthesizing Sn-Cu@Sn dendrites that have a core@shell architecture. The Sn-Cu@Sn dendrites were prepared by a scalable electro-deposition method. The electronic structure was modified to suppress a reaction pathway for CO production on the Sn surface. Notably, the Sn shell inhibited the cathodic corrosion of Cu during the CO2RR. On a gas diffusion electrode, the Sn-Cu@Sn dendrites exhibited 84.2% faraday efficiency to formic acid for 120 h with high stability.

Photo-assisted electrochemical CO2 reduction using a translucent thin film electrode.

Herein, we introduce a new concept of photo-assisted electrochemical CO2 reduction through a translucent thin film electrode. The light-compatible thin film electrode directly exposes Au nanoparticle-loaded Ag nanowires to gaseous CO2, obtaining a CO production rate of 0.7 mmol cm-2 h-1 with a photocurrent density of 6.05 mA cm-2 at -1.1 VRHE.

Design Principles of NiFe-Layered Double Hydroxide Anode Catalysts for Anion Exchange Membrane Water Electrolyzers.

Much effort has been devoted to developing electrocatalysts applicable to anion exchange membrane water electrolyzers (AEMWEs). Among many candidates for oxygen evolution reaction, NiFe-layered double hydroxide (LDH)-based electrocatalysts show the highest activity in an alkaline medium. Unfortunately, the poor electrical conductivity of NiFe-LDH limits its potential as an electrocatalyst, which was often solved by hybridization with conductive carbonaceous materials. However, we find that using carbonaceous materials for anodes has detrimental effects on the stability of AEMWEs at industrially relevant current densities. In this work, a facile monolayer structuring is suggested to overcome low electrical conductivity and improve mass transport without using carbonaceous materials. The monolayer NiFe-LDH deposited on Ni foam showed much better AEMWE performance than conventional bulk NiFe-LDH due to better electrical conductivity and higher hydrophilicity. A high energy conversion efficiency of 72.6% and outstanding stability at a current density of 1 A cm-2 over 50 h could be achieved without carbonaceous material. This work highlights electrical conductivity and hydrophilicity of catalysts in membrane-electrode-assembly as key factors for high-performance AEMWEs.

Anatomic double-bundle medial patellofemoral ligament reconstruction with aperture fixation using an adjustable-length loop device: a 2-year follow-up study.

BACKGROUND: To assess the clinical availability of an adjustable-length loop device for use in the double-bundle technique with aperture fixation at the patella and femur during anatomic double-bundle medial patellofemoral ligament reconstruction (DB-MPFLR) for recurrent patellar dislocation. METHODS: We retrospectively investigated 11 patients (12 knees) with recurrent patellar dislocation who underwent anatomic DB-MPFLR with an ipsilateral semitendinosus tendon autograft. The graft was folded in half, and its central portion was hanged using the adjustable-length loop device. Both free ends of the graft were fixed at the proximal and distal ends of the medial edge of the patella by using suture anchors, and the hanged graft loop was pulled into the femoral tunnel while maintaining equal tension on both bundles. Manual traction of the suture loops was applied to fix the graft appropriately in full range of motion (ROM) of the knee joint under arthroscopic guidance. Clinical outcomes such as re-dislocation, ROM, clinical scores (Kujala score, Lysholm score, and visual analogue scale score for anterior knee pain), and complications were assessed preoperatively and at 2 years postoperatively. Radiographic parameters indicating patellar position, including congruence angle and lateral patellofemoral angle, were measured at 4 different angles of knee flexion (30°, 45°, 60°, and 90°). RESULTS: At 4 different flexion angles of the knee joint, the preoperative congruence angle decreased significantly and the lateral patellofemoral angle increased significantly at the final follow-up (P <  0.001). Notably, the improvements in these angles were maintained with no significant differences at the 4 different flexion angles. None of the patients experienced subluxation or re-dislocation after surgery. The patellar instability symptoms improved, as confirmed on the basis of radiographic and other clinical outcomes. CONCLUSION: New DB technique with aperture fixation at the patella and femur by using an adjustable-length loop device offers high stability with full ROM of the knee joint, can be considered as a feasible procedure and technique for recurrent patellar dislocation.

Balancing activity, stability and conductivity of nanoporous core-shell iridium/iridium oxide oxygen evolution catalysts.

The selection of oxide materials for catalyzing the oxygen evolution reaction in acid-based electrolyzers must be guided by the proper balance between activity, stability and conductivity-a challenging mission of great importance for delivering affordable and environmentally friendly hydrogen. Here we report that the highly conductive nanoporous architecture of an iridium oxide shell on a metallic iridium core, formed through the fast dealloying of osmium from an Ir25Os75 alloy, exhibits an exceptional balance between oxygen evolution activity and stability as quantified by the activity-stability factor. On the basis of this metric, the nanoporous Ir/IrO2 morphology of dealloyed Ir25Os75 shows a factor of ~30 improvement in activity-stability factor relative to conventional iridium-based oxide materials, and an ~8 times improvement over dealloyed Ir25Os75 nanoparticles due to optimized stability and conductivity, respectively. We propose that the activity-stability factor is a key "metric" for determining the technological relevance of oxide-based anodic water electrolyzer catalysts.

Identification of Osteoporosis-Associated Protein Biomarkers from Ovariectomized Rat Urine.

OBJECTIVE: Osteoporotic fracture is one of the most common health risks and aggravates the quality of life among postmenopausal women worldwide. In this study, osteoporosis-associated protein biomarkers were identified from urine of osteoporotic female Sprague-Dawley rats developed by ovariectomy. METHOD: Four months after the operation, the bone mineral density of the femur of ovariectomized rats was significantly lowered in comparison with that of the sham operated rats. The protein profiles of the urine samples collected from the sham, ovariectomized (OVX) and 2 month-old non-operated (Young) rats were compared by 2-D gel and MS spectrometry. RESULTS: Proteins consistently expressed between Young and sham but differentially expressed in OVX rats were selected and identified. One down-regulated 21 kDa protein, superoxide dismutase (SOD), and 1 up-regulated 53-54 kDa protein, alph-1-antitrypsin (A1AT), were selected from urine of the ovariectomized rats by 2-D gel analysis. Further, a total of 30 with 19 up-regulated and 11-down-regulated proteins were selected by LC-MS analysis with more than 2-fold differences in spectral counts. The fact that SOD and A1AT are also listed in the 30 differential proteins suggests that our biomarker isolation procedure suitably represents osteoporosis-associated proteins in urine. CONCLUSION: Supporting the facts, the differential expressions of SOD and A1AT in urine could be validated by Western blotting. These urinary osteoporosis-associated proteins have high potentials to become candidates for non-invasive diagnosis of osteoporosis from urine.

Shaped Ir-Ni bimetallic nanoparticles for minimizing Ir utilization in oxygen evolution reaction.

Shaped Ir-Ni bimetallic nanoparticles were synthesized and used for electrocatalytic oxygen evolution reaction (OER). The obtained bimetallic nanoparticles showed significantly enhanced Ir mass activity and durability compared with Ir nanoparticles.

Propofol-ketamine or propofol-remifentanil for deep sedation and analgesia in pediatric patients undergoing burn dressing changes: a randomized clinical trial.

OBJECTIVE: In this study, we compared the propofol-ketamine and propofol-remifentanil combinations for deep sedation and analgesia during pediatric burn wound dressing changes. METHODS: Fifty pediatric patients aged 12-36 months, undergoing burn wound dressing changes, were randomly assigned to receive propofol-remifentanil (group PR) or propofol-ketamine (group PK) for deep sedation and analgesia. Patients in the group PR received 2 mg·kg(-1) propofol and 0.1 µg·kg(-1) remifentanil, and 0.05 µg·kg(-1) ·min(-1) remifentanil was infused continuously until the end of the procedure. Patients in the group PK received 2 mg·kg(-1) propofol and 1 mg·kg(-1) ketamine, and the same volume of isotonic saline was infused continuously until the end of the procedure. Additional propofol with remifentanil or ketamine was administered when required. Hemodynamic variables, drug requirements, occurrence of patient movement, surgeon's satisfaction score, recovery time, and the incidence of adverse events were recorded throughout the procedure and recovery. RESULTS: Recovery time was significantly shorter in the group PR compared to that in the group PK (10.3 [9.1-11.5] min vs 22.5 [20.3-25.6] min, median [interquartile range], respectively; P < 0.001). No significant hypotension or bradycardia occurred throughout the procedure. No significant differences were observed in terms of drug requirements, occurrence of patient movement, surgeon's satisfaction, incidence of respiratory depression, hypoxia, or nausea and vomiting CONCLUSIONS: The combinations of propofol-ketamine and propofol-remifentanil were effective for sedation and analgesia in pediatric patients undergoing burn dressing changes, but the propofol-remifentanil combination provided faster recovery compared to the propofol-ketamine combination.

The influence of post-operative surveillance on the prognosis after curative surgery for gastric cancer.

BACKGROUND/AIMS: Although routine post-operative surveillance after curative resection for gastric cancer is recommended, there are few reports on the value of postoperative follow-up. The aim of this study was to assess the possible role of post-operative surveillance as a prognostic factor after curative resection for gastric cancer. METHODOLOGY: A total of 192 gastric cancer patients who suffered recurrences after curative resection between January 2001 and June 2012 were included in this study. Clinicopathological factors and survival were retrospectively analyzed according to the presence or absence of symptoms related to tumor recurrence at the time of relapse. RESULTS: One-hundred-and-twenty-six of the patients (65.6%) had asymptomatic recurrences. Peritoneal recurrence (60.6%) predominated among the symptomatic recurrences, whereas locoregional recurrences (42.1%) were dominant among the asymptomatic recurrence. Median recurrence-free survival times did not differ between the two groups (p=0.507). However, median post-recurrence (p<0.001) and overall survival times (p=0.022) were longer in the asymptomatic group. CONCLUSIONS: Time to recurrence did not differ between the symptomatic and asymptomatic recurrence groups, but post-recurrence survival and overall survival were better in the asymptomatic group. Prior to the execution of a large scale randomized controlled trial, close follow-up should be considered.

Improved spatial learning and memory by perilla diet is correlated with immunoreactivities to neurofilament and α-synuclein in hilus of dentate gyrus.

BACKGROUND: Perilla (Perilla frutescens) oil is very rich in α-linolenic acid, an omega-3 fatty acid. As it is widely reported that omega-3 fatty acid supplementation improves cognitive function in children and adults, feeding rats with perilla diets followed by analysis of proteomic changes in the hippocampus can provide valuable information on the mechanism of learning and memory at the molecular level. To identify proteins playing roles in learning and memory, differentially expressed proteins in the hippocampus of the 5 week old rats fed perilla diets for 3 weeks or 3 months were identified by proteomic analysis and validated by immunological assays. RESULTS: The perilla diet groups showed improved spatial learning and memory performances in a T-maze test. They also displayed elevated level of 22:6n-3 fatty acid, an omega-3 fatty acid (p<0.05), in the brain compared to the control diet group. Quantitative proteomic analysis using 2-D gels as well as functional annotation grouping with the differentially expressed proteins in the hippocampus showed that those proteins involved in cytoskeleton and transport were the major differentially expressed proteins in the 3-week group, whereas those involved in energy metabolism, neuron projection and apoptosis in addition to cytoskeleton and transport were the major ones in the 3 month group. Differential protein expression in the hippocampus was validated by Western blotting using four selected proteins, known to be involved in synaptic plasticity; AMPA receptor, neurofilament, α-synuclein, and ß-soluble NSF attachment protein. Brain sections from the perilla-diet groups showed enhanced immunoreactivities to α-synuclein and neurofilament. Especially, neurofilament immunoreactive cells manifested longer neurite projections in the hilus of dentate gyrus of the perilla-diet groups. CONCLUSION: Improved cognitive function upon administration of n-3 fatty acid-rich perilla diet is associated with the differential expression of hippocampal proteins related to cytoskeleton, energy metabolism, transport, neuro-projection, and apoptosis. Particularly, the enhanced immunoreactivities to α-synuclein and neurofilament in the hilus of dentate gyrus suggest that perilla diet supplementation promotes neuronal signaling and alters synaptic plasticity for improved learning and memory.

Cloning and expression of a bpr gene encoding Bacillopeptidase F from Bacillus amyloliquefaciens CH86-1.

A gene encoding bacillopeptidase F, bpr86-1, was cloned from B. amyloliquefaciens CH86-1 isolated from cheonggukjang. This gene could encode a preproenzyme of 1,431 amino acids. When bpr86-1 was introduced into B. subtilis WB600 via pHY300PLK, an E. coli-Bacillus shuttle vector, the transformant showed fibrinolytic activity. During growth on LB, the fibrinolytic activity of cells increased sharply when they entered the stationary phase. The highest activity (761.4 mU/mg protein) was observed at 96 h of cultivation.

A RAPD-PCR method for the rapid detection of Bacillus cereus.

Distinction of Bacillus cereus from other closely related bacilli is challenging and new efficient methods are continually demanded. From our previous work on RAPD profiles of bacilli, we found a possibility that B. cereus strains could be distinguished from other bacilli. In this work, RAPD-PCR profiles of B. cereus strains were obtained using a 10-mer (S30) as a primer, and a B. cereus specific 0.91-kb band was produced from all tested strains. The RAPD-PCR procedure also successfully detected B. cereus from spiked cheonggukjang when B. cereus cells were present at more than 10(2)/g sample.

Simultaneous enhancement of free isoflavone content and antioxidant potential of soybean by fermentation with Aspergillus oryzae.

In order to determine the fungal strain and fermentation period which produce the highest antioxidant activity of fermented soy product, soybean was fermented with Aspergillus oryzae NL 5 isolated from Korean traditional meju produced in Sunchang Yeastopia Land in Korea, and was subjected to analyzing isoflavone profiles and assaying antioxidant activity. Antioxidant potential of the samples was evaluated by ferric reducing antioxidant power assay, 2,2'-azinobis (2-ethylbenzthiazoline-6-sulfonic acid) radical scavenging activity and total phenolic contents. In addition, antioxidant assay using fluorescent probes, 2',7'-dichlorofluorescin diacetate and dihydroethidium, in HepG2 cells was conducted for the samples. The results showed that both high isoflavone variety Aga 3 and medium isoflavone variety Daewon of soybean fermented with Asp oryzae NL5 for 4 to 5 d showed the highest increase in free isoflavone contents, together with the highest antioxidant activity. In conclusion, the antioxidant activity of fermented soy was proportional to the concentration of free isoflavones, and was significantly influenced by total isoflavone content of soybean variety and fermentation period. Practical Application: Isoflavone profile and antioxidant capacity of soybean were widely variable during fermentation with Asp oryzae, and thereby it is recommended that meju (or koji) preparation condition, in particular, fermentation time is carefully optimized to maximize the antioxidant capacity of soy products fermented by Asp oryzae.

Isolation and characterization of a novel thermostable alpha-amylase from Korean pine seeds.

Amylases have significant importance in broad industrial application including bio-ethanol production. Although amylases are widely distributed in microbes, plants and animals, it has been sought for new amylases from various sources with special industrial potential. In this study we firstly isolated and characterized a novel thermostable alpha-amylase from Korean pine seed. Enzyme was purified to homogeneity level with purification fold of 1286.1 using several techniques such as self-precipitation, (NH(4))(2)SO(4) fractionation, DEAE anion exchange and starch affinity chromatography. The purified alpha-amylase showed two bands in SDS-PAGE with molecular weight of 44 and 45 kDa. The apparent molecular weight of native enzyme was calculated to be 46.7 kDa. Internal peptide sequencing confirmed that the purified alpha-amylase was a novel enzyme. The optimum pH and temperature for enzyme activity were pH 4.5 and 65 degrees C, respectively. This enzyme was fully stable for 48h at 50 degrees C and retained 80% activity up to 96h. The K(m) and V(max) were 0.84 mg/ml and 3.71 micromol/min, respectively. On the basis of high thermal stability and a broad range of pH stability, the pine seed alpha-amylase showed a good prospect of industrial application.

Development of a RAPD-PCR method for identification of Bacillus species isolated from Cheonggukjang.

A RAPD-PCR (Randomly Amplified Polymorphic DNA-PCR) method was developed for rapid identification of Bacillus species, especially B. subtilis, B. licheniformis, and B. amyloliquefaciens, the most frequently isolated organisms from fermented soy foods such as Cheonggukjang, a Korean traditional food. A RAPD-PCR using a 10-mer (S-30) produced species specific bands reproducibly. All B. subtilis strains tested produced common bands of 0.5 and 0.88 kb in size. All B. amyloliquefaciens strains generated 1.1 and 1.5 kb bands together with 0.5 kb fragment whereas B. licheniformis strains produced 1.25, 1.70, and 1.9 kb bands with an occasional 0.5 kb band. Using the RAPD-PCR protocol, six bacilli strains isolated from Cheonggukjang were identified to the species level, which was difficult by 16S rRNA gene and recA gene sequencing for some isolates. The 0.5 kb fragment, the major band for B. subtilis strains, was an internal part of a ytcP gene encoding a hypothetical ABC-type transporter. A B. subtilis species specific primer pair was designed based on ytcP sequences and PCR using the primer pair produced a 0.46 kb fragment only from B. subtilis strains.

PGK1 induction by a hydrogen peroxide treatment is suppressed by antioxidants in human colon carcinoma cells.

Few protein biomarkers for oxidative stress have been reported. In this study, we attempted to identify the proteins selectively overexpressed in human colon tumor cells by treating with hydrogen peroxide as oxidative stress. A proteomic analysis followed by western blotting showed that phosphoglycerate kinase 1 (PGK1) was induced by hydrogen peroxide in a dose-dependent manner, while its expression was suppressed by a co-treatment with delphinidin, a known antioxidant. Furthermore, several antioxidants, including alpha-tocopherol, butylated hydroxytoluene (BHT), and Trolox, also inhibited the PGK1 induction caused by hydrogen peroxide. The data suggest that PGK1 might be a potential protein biomarker of intracellular oxidative status.