A multi-functional reagent suitable for 1-step rapid DNA intercalation fluorescence-based screening of total bacteria in drinking water.

The prerequisites for rapid screening of total bacteria in drinking water are low detection limit and convenience. Inspired by commercial adenosine 5'-triphosphate (ATP) based total bacterial detection kits, we pursued likewise convenience but with much lower detection limit. Existing intercalation fluorescence-based techniques employ multiple reagents to permeate the cell membrane and intercalate dye into the DNA in discrete sequential steps. A simple multi-functional reagent is proposed to do the same within one step. Surfactants (TritonX and SDS), and intercalating dyes (SYBR green, SYBR gold) were examined for their mutual compatibility and augmented with EDTA. Evaluation was performed with Gram negative Escherichia coli K12 (E. coli K12) and Gram positive Bacillus subtilis (B. subtilis) at serial dilution ratios from 10-6 to 10-2. Comparison was made with absorbance (600 nm) measurements and a commercial ATP kit. Using charge integrated photodetection, the proposed 1-step reagent achieved an LOD (1.00 × 10-6, B. subtilis) that is two orders of magnitude lower than that of ATP kit (LOD = 1.06× 10-4). This means it could detect minute quantity of total bacteria that is otherwise undetected by the ATP kit.

Tuning the C1 /C2 Selectivity of Electrochemical CO2 Reduction on Cu-CeO2 Nanorods by Oxidation State Control.

Ceria (CeO2 ) is one of the most extensively used rare earth oxides. Recently, it has been used as a support material for metal catalysts for electrochemical energy conversion. However, to date, the nature of metal/CeO2 interfaces and their impact on electrochemical processes remains unclear. Here, a Cu-CeO2 nanorod electrochemical CO2 reduction catalyst is presented. Using operando analysis and computational techniques, it is found that, on the application of a reductive electrochemical potential, Cu undergoes an abrupt change in solubility in the ceria matrix converting from less stable randomly dissolved single atomic Cu2+ ions to (Cu0 ,Cu1+ ) nanoclusters. Unlike single atomic Cu, which produces C1 products as the main product during electrochemical CO2 reduction, the coexistence of (Cu0 ,Cu1+ ) clusters lowers the energy barrier for C-C coupling and enables the selective production of C2+ hydrocarbons. As a result, the coexistence of (Cu0 ,Cu1+ ) in the clusters at the Cu-ceria interface results in a C2+ partial current density/unit Cu weight 27 times that of a corresponding Cu-carbon catalyst under the same conditions.

Aminoacyl transfer ribonucleic acid synthetase complex-interacting multifunctional protein 1 induces microglial activation and M1 polarization via the mitogen-activated protein kinase/nuclear factor-kappa B signaling pathway.

Activation of microglia, which is the primary immune cell of the central nervous system, plays an important role in neuroinflammation associated with several neuronal diseases. Aminoacyl tRNA synthetase (ARS) complex-interacting multifunctional protein 1 (AIMP1), a structural component of the multienzyme ARS complex, is secreted to trigger a pro-inflammatory function and has been associated with several inflammatory diseases. However, the effect of AIMP1 on microglial activation remains unknown. AIMP1 elevated the expression levels of activation-related cell surface markers and pro-inflammatory cytokines in primary and BV-2 microglial cells. In addition to the AIMP1-mediated increase in the expression levels of M1 markers [interleukin (IL)-6, tumor necrosis factor-α, and IL-1ß], the expression levels of CD68, an M1 cell surface molecule, were also increased in AIMP-1-treated microglial cells, while those of CD206, an M2 cell surface molecule, were not, indicating that AIMP1 triggers the polarization of microglial cells into the M1 state but not the M2 state. AIMP1 treatment induced the phosphorylation of mitogen-activated protein kinases (MAPKs), while MAPK inhibitors suppressed the AIMP1-induced microglial cell activation. AIMP1 also induced the phosphorylation of the nuclear factor-kappa B (NF-κB) components and nuclear translocation of the NF-κB p65 subunit in microglial cells. Furthermore, c-Jun N-terminal kinase (JNK) and p38 inhibitors markedly suppressed the AIMP1-induced phosphorylation of NF-κB components as well as the nuclear translocation of NF-κB p65 subunit, suggesting the involvement of JNK and p38 as upstream regulators of NF-κB in AIMP1-induced microglial cell activation. The NF-κB inhibitor suppressed the AIMP1-induced M1 polarization of the microglial cells. Taken together, AIMP1 effectively induces M1 microglial activation via the JNK and p38/NF-κB-dependent pathways. These results suggest that AIMP1 released under stress conditions may be a pathological factor that induces neuroinflammation.

Single Intramuscular-dose Toxicity of Water soluble Carthmi-Flos herbal acupuncture (WCF) in Sprague-Dawley Rats.

OBJECTIVES: This experiment was conducted to examine the toxicity of Water soluble Carthmi-Flos herbal acupuncture (WCF) by administering a single intramuscular dose of WCF in 6-week-old, male and female Sprague-Dawley rats and to find the lethality dose for WCF. METHODS: The experiment was conducted at Biotoxtech according to Good Laboratory Practices under a request by the Korean Pharmacopuncture Institute. This experiment was performed based on the testing standards of "Toxicity Test Standards for Drugs" by the Ministry of Food and Drug Safety. Subjects were divided into 4 groups: 1 control group in which normal saline was administered and 3 test groups in which 0.1, 0.5 or 1.0 mL of WCF was administered; a single intramuscular dose was injected into 5 males and 5 females in each group. General symptoms and body weights were observed/measured for 14 days after injection. At the end of the observation period, hematological and clinical chemistry tests were performed, followed by necropsy and histopathological examinations of the injected sections. RESULTS: No mortalities were observed in any group. Also, symptoms, body weight, hematology, clinical chemistry and necropsy were not affected. However, histopathological examination of the injected part in one female in the 1.0-mL group showed infiltration of mononuclear cells and a multi-nucleated giant cell around eosinophilic material. CONCLUSION: Administration of single intramuscular doses of WCF in 3 groups of rats showed that the approximate lethal dose of WCF for all rats was in excess of 1.0 mL, as no mortalities were observed for injections up to and including 1.0 mL.

Single Intramuscular-dose Toxicity of Anti-inflammatory Pharmacopuncture in Rats.

OBJECTIVES: This study was performed to analyze the toxicity of the test substance, anti-inflammatory pharmacopuncture (AIP), when used as a single intramuscular-dose in 6-week-old, male and female Sprague-Dawley rats and to find the lethal dose. METHODS: The experiment was conducted at Biotoxtech according to Good Laboratory Practices. Twenty (20) female and 20 male Spague-Dawley rats were divided into 4 groups of five 5 female and 5 male animals per group. The rats in the three experimental groups received single intramuscular injections with 0.1-㎖, 0.5-㎖ and 1.0-㎖/animal doses of AIP, Groups 2, 3, and 4, respectively, and the control group, Group 1, received a single intramuscular injection with a 1.0-㎖ dose of normal saline. Clinical signs were observed and body weight measurements were carried out for 14 days following the injections. At the end of the observation period, hematology, clinical chemistry, histopathological tests and necropsy were performed on the injected parts. RESULTS: No deaths occurred in any of the groups. Also, histopathological tests showed that AIP had no effect on the injected parts in terms of clinical signs, body weight, hematology, clinical chemistry, and necropsy. CONCLUSIONS: As a result of single intramuscular-dose tests of the test substance AIP in 4 groups of rats, the lethal dose for both males and females exceeded 1.0㎖/animal. Therefore, AIP is a relatively safe pharmacopuncture that can be used for treatment, but further studies should be performed.