Optimization of cyclosporin A production by Beauveria nivea in continuous fed-batch fermentation

To develop the effective control method for fed-batch culture of cyclosporin A production, we chose fructose, L-valine and (NH4)2HPO4 as feeding nutrients and compared their productivities in relation to different concentrations. The feeding rate of three kinds of feeding materials was controlled to maintain the suitable residual concentration. The fed-batch fermentation results indicated that the optimal concentrations of fructose, L-valine and (NH4)2HPO4 were about 20 g/L, 0.5 g/L and 0.6 g/L for cyclosporin A production, respectively. The cultivation of Beauveria nivea could produce cyclosporin A up to 6.2 g/L for 240 hrs through a continuous feeding-rate-controlled-batch process under the optimal feeding conditions

Ginsenosides are novel naturally-occurring aryl hydrocarbon receptor ligands.

The aryl hydrocarbon receptor (AHR) is a ligand-dependent transcription factor that mediates many of the biological and toxicological actions of structurally diverse chemicals. In this study, we examined the ability of a series of ginsenosides extracted from ginseng, a traditional Chinese medicine, to bind to and activate/inhibit the AHR and AHR signal transduction. Utilizing a combination of ligand and DNA binding assays, molecular docking and reporter gene analysis, we demonstrated the ability of selected ginsenosides to directly bind to and activate the guinea pig cytosolic AHR, and to stimulate/inhibit AHR-dependent luciferase gene expression in a recombinant guinea pig cell line. Comparative studies revealed significant species differences in the ability of ginsenosides to stimulate AHR-dependent gene expression in guinea pig, rat, mouse and human cell lines. Not only did selected ginsenosides preferentially activate the AHR from one species and not others, mouse cell line was also significantly less responsive to these chemicals than rat and guinea pig cell lines, but the endogenous gene CYP1A1 could still be inducted in mouse cell line. Overall, the ability of these compounds to stimulate AHR signal transduction demonstrated that these ginsenosides are a new class of naturally occurring AHR agonists

Vapor-phase hydrothermal synthesis of rutile TiO2 nanostructured film with exposed pyramid-shaped (111) surface and superiorly photoelectrocatalytic performance

Rutile TiO2 nanostructured film with exposed pyramid-shaped (111) surface was successfully fabricated using metal titanium foil as substrate through a facile vapor-phase hydrothermal method. The fabricated rutile TiO2 film was composed of vertically aligned rod-like structures with diameters ranged from 400 to 700 nm and thickness of ca. 2.0 孮 The obtained rutile TiO2 film as photoanode exhibited excellent photoelectrocatalytic activity toward water oxidation and rhodamine B decolorization under UV illumination, which was more than 3.5 and 1.2 times of that obtained by highly ordered anatase TiO2 nanotube array film photoanode under the same experimental conditions, respectively. The excellent photoelectrocatalytic performance of the rutile TiO2 film photoanode could be due to the superior photoelectron transfer property and the high oxidative capability of {111} crystal facets. The superior photoelectron transfer capability of the photoanodes was manifested by the inherent resistance (R0) of the photoanodes using a simple photoelectrochemical method. The calculated R0 values were 50.5 and 86.2 O for the rutile TiO2 nanostructured film and anatase TiO2 nanotube array film, respectively. Lower R0 value of the rutile TiO2 photoanode indicated a superior photoelectron transfer capability owing to good single crystal property of the rod-like rutile nanostructure. Almost identical valence band level (1.94 eV) of the rutile TiO2 nanostructured film and anatase TiO2 nanotube array film (meaning a similar oxidation capability) further confirmed the significant role of photoelectron transfer capability and exposed high-energy {111} crystal facets for improved photoelectrocatalytic performance of the rutile TiO2 nanostructured film photoanode.No Full Tex

Development of an electrochemical flow injection immunoassay (FIIA) for the real-time monitoring of biospecific interactions

Not only are sensors a revolution in analysis; they themselves are also experiencing a revolution brought about by parallel developments in sensor fabrication techniques and materials, polymer chemistry, signal processing methodologies, the increased use of biomolecular processes as a means of analyte detection, and the coupling of sensors to other techniques such as flow injection analysis. Many of these developments have been incorporated into the present study, which we are undertaking in the development of our immunosensor technology. The system described here utilises screen-printed electrodes which are low-cost, disposable devices that are simple to fabricate. Incorporated into our sensor is the electroactive polymer, polyaniline, which brings about mediatorless redox coupling between the electrode and biomolecular components attached to the polymer surface. This system also utilises enzyme-labelled antibodies as the biomolecular recognition component for the analysis of the test analyte, biotin. The system has also been integrated into a flow injection system. This has led to the monitoring of real-time antibody-antigen interactions using electrochemical methods and foreshadows the development of single-step immunosensors

Role of Atmosphere-ocean-ice Interaction in the Linkage between December Bering Sea Ice and Subsequent February Surface Air Temperature Over North America

Under embargo until 2023-08-16This study revealed that the interannual variations of December Bering Sea ice and subsequent February surface air temperature (SAT) over North America are significantly correlated during 2000/01-2020/21, which is not the case during 1966/67-1999/2000. During 2000/01-2020/21, reduced December Bering Sea ice is generally followed by a February meridional dipole pattern in the atmospheric circulation over North America, which provides favorable conditions for colder temperatures. Further analysis elucidates that the intensified persistence of December Bering Sea ice anomaly might be responsible for the identified change in such a lead-lag sea ice-SAT linkage. During 2000/01-2020/21, the Bering Sea ice anomaly in December can persist into the subsequent February during which the Bering Sea ice anomaly can stimulate an eastward-propagating Rossby wave train propagating to North America and causing the meridional dipole pattern. The longer persistence of December Bering Sea ice anomaly during 2000/01-2020/21 is attributed to the interdecadal intensified atmosphere-ocean-ice interaction over the Bering Sea - a positive feedback loop that favors the persistence of Bering Sea ice anomaly. A negative sea-ice concentration anomaly with more open water in the Bering Sea would allow the ocean to release more heat and warm more the air aloft. This will lead to more downward longwave radiation, preventing the winter sea ice growth and helping maintain the Bering Sea ice anomaly. Results of this study indicates that the intensity of atmosphere-ocean-ice interaction in the Bering Sea may modulate the linkage between the February SAT over North America and the preceding December Bering Sea ice.publishedVersio

Chondroitin polymerizing factor (CHPF) promotes the progression of colorectal cancer through ASB2-mediated ubiquitylation of SMAD9

Chondroitin polymerizing factor (CHPF) has been reported to play a pivotal role in the progression of multiple cancers, however, the relationship between CHPF and colorectal cancer (CRC) progression has not been fully understood. The current study revealed that CHPF expression was upregulated in patients with CRC and correlated with an unfavorable prognosis. Also, CHPF knockdown effectively suppressed the viability and mobility of CRC cells and the growth of xenograft tumors. Additionally, SMAD9 was identified as a downstream target of CHPF. SMAD9 knockdown successfully abrogated the promotion of CHPF overexpression in CRC progression, indicating that CHPF regulated the development of CRC through SMAD9. Mechanistically, SMAD9 is ubiquitinated by ASB2, and the regulatory effect of CHPF on SMAD9 activity was exerted via its mediation of ASB2. Collectively, CHPF functioned as a promising prognostic biomarker and tumor-promoter of CRC by regulating the ASB2-mediated ubiquitination of SMAD9