Cobalt metal-mixed organic complex-based hybrid micromaterials: ratiometric detection of cyanide

A micrometer-sized hybrid crystalline material was facilely fabricated from the synergistic coordination chemistry of two types of 2-hydroxyazobenzene building blocks and cobalt ions. This hybrid crystalline material functioned as both receptor and signal reporter in cyanide (CN⁻) sensing with ratiometric absorption responses at 456 nm and 537 nm. The mechanism of CN⁻ sensing involves partial ligand dissociation accompanied by the formation of a new organic metal–CN⁻ adduct. We believe that this protocol would be valuable in achieving the expected selectivities and sensitivities for a wide variety of analytes in many chemical and biological systems in the future.

A cobalt metal-mixed organic complex-based hybrid micromaterial has been presented to detect CN⁻ with ratiometric absorption responses (A_{456 nm}/A_{537 nm}).     

Laccase immobilization and surface modification of activated carbon fibers by bio-inspired poly-dopamine

In this study, we developed a new synthesis method for modifying activated carbon fibers (ACFs) by dopamine with oxidation-based self-polymerization (DA-ACFs). In addition, laccase was immobilized on the surface of unmodified ACFs (L-ACFs) and DA-ACFs (LDA-ACFs) via cross-linking after being incubated for 12 h at 5 °C. The surface composition and microstructure of the samples were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, attenuated total reflectance Fourier-transform infrared reflection and thermo-gravimetric analysis. The optimized laccase concentration for preparing the samples was 2.0 g L⁻¹. The results demonstrated that the successful poly-dopamine modification increased the catalytic abilities of the ACFs in terms of biocompatibility and hydrophilicity. Compared with free laccase, the immobilized laccase exhibited significantly higher relative activity over a pH range of 3.5–6.5 and a temperature range of 30–60 °C; the thermo-stability increased, and 50% relative activity of the LDA-ACFs remained after 5 h at 55 °C. After six cycles of reuse, the relative activity of LDA-ACFs remained ≥60%, compared to 40% activity remaining for L-ACFs, and long-term storage stability was demonstrated. Moreover, the kinetic parameters (K_m) of the two immobilized laccases were both higher than that of free laccase, whereas the maximum velocities (V_max) were lower. These results indicate that the DA-ACFs are economical, simple, and efficient carries for enzyme immobilization, and can be suitable for further biotechnology and environmental applications.

In this study, we developed a new synthesis method for modifying activated carbon fibers (ACFs) by dopamine with oxidation-based self-polymerization (DA-ACFs).     

Risk factors for latent tuberculosis infection in children in South Korea

Objectives: In South Korea, latent tuberculosis infection (LTBI) screening is a critical strategy associated with efforts to reduce the incidence of tuberculosis (TB). Currently, only children with a known history of TB contact are considered as pediatric high-risk groups for LTBI, and consequently, LTBI screening is only provided to these children. However, to reduce the incidence of TB, the high-risk groups that undergo LTBI screening should be expanded. This study aimed to assess the risk factors for LTBI among children living in South Korea with no known history of TB contact for the identification of additional high-risk groups. We investigated the risk factors for LTBI among US visa applicant children, who undergo LTBI screening regardless of their TB contact history.

Methods: We obtained data on demographic characteristics, medical history, Bacillus Calmette–Guerin (BCG) vaccination history, and results of LTBI screening for children aged 2–14 years. A tuberculin skin test was used for the diagnosis of LTBI, and an induration of 10 mm or greater was used to define a positive test. Adjusted odds ratios and 95% confidence intervals were calculated to determine the association between clinical and demographic variables and LTBI.

Results: Of the 1,664 study participants, 91 (5.5%) had LTBI. The binary logistic regression analysis showed that children born in high TB burden foreign countries had the highest odds of LTBI when considering all the risk factors investigated. Increasing age, absence of BCG vaccination, and a previous diagnosis of asthma were also significant risk factors for LTBI.

Conclusion: These results indicate that children born in high TB burden foreign countries should be considered a high-risk group for LTBI in South Korea; the inclusion of these children in LTBI screening should be considered.     

HPLC法测定注射用阿莫西林钠含量的方法研究

目的:建立高效液相色谱法测定注射用阿莫西林钠含量的方法。方法:色谱条件:C18柱,流动相为0.05 mol/L磷酸二氢钾溶液-乙腈(97.5∶2.5),检测波长为254 nm,流速1.0 m L/min,柱温25℃。结果:阿莫西林在0.25 mg/m L~0.75 mg/m L范围内与峰面积呈良好线性关系,平均回收率为99.4%,RSD=0.12%(n=6)。结论:该方法操作简便、快捷,重现性好,可作为注射用阿莫西林钠的含量测定方法。     

An evaluation of single question delirium screening tools in older emergency department patients

Objectives

To determine the diagnostic performances of several single question delirium screens. To the patient we asked: “Have you had any difficulty thinking clearly lately?” To the patient's surrogate, we asked: “Is the patient at his or her baseline mental status?” and “Have you noticed the patient's mental status fluctuate throughout the course of the day?”

Dietary polyphenol canolol from rapeseed oil attenuates oxidative stress-induced cell damage through the modulation of the p38 signaling pathway

Canolol (CAO) is a main phenolic compound with remarkable antioxidative properties that is generated in rapeseed oil during microwave pressing. The objective of this study was to identify the protective effect of CAO in hydrogen peroxide (H₂O₂)-triggered oxidative stress and reveal the role of the p38 MAPK pathway during the protective process. CAO treatment showed an observable cytoprotective effect. Results showed that CAO significantly improved H₂O₂-stimulated cell death, and diminished ROS production and malondialdehyde (MDA) level. Moreover, CAO increased glutathione (GSH) content and promoted the activities of superoxide dismutase (SOD) and catalase (CAT). As a result, apoptosis was ameliorated and depletion of the mitochondrial membrane potential was restored. Western blotting analysis demonstrated CAO downregulated the expression of caspase-3 and decreased the ratio of Bax/Bcl-2. Notably, the phosphorylation of p38 MAPK was inhibited by CAO in H₂O₂-induced apoptosis, which was confirmed by its inhibitor (SB203580). Taken together, our study demonstrated the pivotal role of the p38 MAPK pathway in the cytoprotective effect of CAO on oxidative stress-induced cell damage, suggesting CAO is a promising antioxidant in food and health-related fields.

Canolol extracted from rapeseed oil attenuated oxidative stress-induced apoptosis and cellular redox status imbalance by inhibition of p38 phosphorylation.