Real-time reconstruction using electro-optics modulator-based structured illumination microscopy.

Structured illumination microscopy (SIM), a super-resolution technology, has a wide range of applications in life sciences. In this study, we present an electro-optic high-speed phase-shift super-resolution microscopy imaging system including 2D SIM, total internal reflection fluorescence-SIM, and 3D SIM modes. This system uses galvanometers and an electro-optic modulator to flexibly and quickly control the phase and direction of structured illumination patterns. Moreover, its design consists of precise timing for improved acquisition speed and software architecture for real-time reconstruction. The highest acquisition rate achieved was 151 frames/s, while the highest real-time super-resolution reconstruction frame rate achieved was over 25 frames/s.

Total variation and spatial iteration-based 3D structured illumination microscopy.

Three-dimensional structured illumination microscopy (3D-SIM) plays an essential role in biological volumetric imaging with the capabilities of improving lateral and axial resolution. However, the traditional linear 3D algorithm is sensitive to noise and generates artifacts, while the low temporal resolution hinders live-cell imaging. In this paper, we propose a novel 3D-SIM algorithm based on total variation (TV) and fast iterative shrinkage threshold algorithm (FISTA), termed TV-FISTA-SIM. Compared to conventional algorithms, TV-FISTA-SIM achieves higher reconstruction fidelity with the least artifacts, even when the signal-to-noise ratio (SNR) is as low as 5 dB, and a faster reconstruction rate. Through simulation, we have verified that TV-FISTA-SIM can effectively reduce the amount of required data with less deterioration. Moreover, we demonstrate TV-FISTA-SIM for high-quality multi-color 3D super-resolution imaging, which can be potentially applied to live-cell imaging applications.

Genistein alleviates H2O2-induced senescence of human umbilical vein endothelial cells via regulating the TXNIP/NLRP3 axis.

CONTEXT: Genistein (Gen) has shown protective effects against ageing process. OBJECTIVE: To explore the role of Gen on the senescence of H2O2-induced human umbilical vein endothelial cells (HUVECs) and investigate the possible mechanism. MATERIALS AND METHODS: HUVECs were treated with different concentrations of H2O2 (50, 100, 200 and 400 µmol/L) for 1 h or Gen administration (20, 40, 80 and 160 µg/mL) for 24 h. Functional experiments (cell counting kit-8, ß-galactosidase staining and flow cytometry) were used to detect the effect of Gen on H2O2-induced HUVECs. After HUVECs were transfected with TXNIP overexpression plasmids, the expression of p16, p21, thioredoxin-interacting protein (TXNIP), nucleotide-binding and oligomerization domain-like receptor 3 (NLRP3), cleaved caspase-3 and cleaved caspase-1 in HUVECs were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. RESULTS: H2O2 (200 and 400 µmol/L) inhibited the proliferation of HUVECs. At concentrations of >50 µmol/L, H2O2 induced the cell cycle progression arrests in G1 phase and promoted cell senescence of HUVECs. Gen had no obvious cytotoxicity to HUVECs below 160 µg/mL. H2O2-induced HUVEC senescence and the expression of TXNIP and NLRP3 in HUVECs were down-regulated by Gen (40 and 80 µg/mL). Expressions of TXNIP and NLRP3 in HUVECs were up-regulated by H2O2 but down-regulated by Gen. Overexpressed TXNIP partially reversed the suppressive effect of Gen on H2O2-induced senescence and apoptosis of HUVECs. Expressions of p16, p21, TXNIP, NLRP3, cleaved caspase-3 and cleaved caspase-1 in H2O2-treated HUVECs were inhibited by Gen, while the inhibition as such was partially reversed by overexpressed TXNIP. DISCUSSION AND CONCLUSIONS: H2O2-induced HUVEC senescence was alleviated by Gen via suppressing the TXNIP/NLRP3 axis, which may offer a potential therapeutic approach for improving HUVEC senescence and provide a new direction for the treatment of cardiovascular disease.

[Chemical Constituents of Ethyl Acetate Fraction from Hypericum ascyron].

Objective: To study the chemical consituents of Hypericum ascyron. Methods: The constituents were isolated and purified by chromatography on silica gel; the structure of the compound was determined by MS and NMR spectral analysis. Results: On the basis of spectroscopic analysis and comparison with the reported data, they were identified as hyperoside( 1),hypercalin B( 2),hypercalin C( 3),1,7-dihydroxyxanthone( 4),2,3-dimethoxyxanthone( 5),1-hydroxy-7-methoxyxanthone( 6),rutin( 7),kaempferol( 8),toxyloxanthone B( 9),quercetin( 10),quercitrin( 11),ß-daucosterol( 12) and ß-sitosterol( 13). Conclusion: Compounds 2,3,6 and 9 are obtained from this plant for the first time.

[Chemical constituents of ethyl acetate fraction from Aeschynanthus bracteatus].

OBJECTIVE: To study the constituents of EtOAc extract from Aeschynanthus bracteatus. METHODS: The constituents were isolated and purified by chromatography on silica gel and the structures of the compounds were determined by MS and NMR spectral analysis. RESULTS: On the basis of spectroscopic analysis and comparison with the reported data, compounds were identified as koaburaside (1), coniferaldehyde (2), syringaldehyde (3), sinapinaldehyde (4), 2,4'-dihydroxyacetophenone (5), piceol (6), beta-daucosterol (7), beta-sitosterol (8). CONCLUSION: Compounds 1 and 2 are obtained from this genus for the first time.

Identification of Cofilin-1 and Destrin as Potential Early-warning Biomarkers for Gamma Radiation in Mouse Liver Tissues.

Gamma radiation causes cell injury and leads to an increased risk of cancer, so it is of practical significance to identify biomarkers for gamma radiation. We used proteomic analysis to identify differentially expressed proteins in liver tissues of C57BL/6J mice treated with gamma radiation from Cs for 360 d. We confirmed obvious pathological changes in mouse liver tissues after irradiation. Compared with the control group, 74 proteins showed a fold change of ≥1.5 in the irradiated groups. We selected 24 proteins for bioinformatics analysis and peptide mass fingerprinting and found that 20 of the identified proteins were meaningful. These proteins were associated with tumorigenesis, tumor suppression, catalysis, cell apoptosis, cytoskeleton, metabolism, gene transcription, T-cell response, and other pathways. We confirmed that both cofilin-1 and destrin were up regulated in the irradiated groups by western blot and real-time polymerase chain reaction. Our findings indicate that cofilin-1 and destrin are sensitive to gamma radiation and may be potential biomarkers for gamma radiation. Whether these proteins are involved in radiation-induced tumorigenesis requires further investigation.

Synthesis of 3-Substituted Aryl[4,5]isothiazoles through an All-Heteroatom Wittig-Equivalent Process.

Extending the previous use of tert-butyl sulfoxide as the sulfinyl source, intramolecular sulfinylation of sulfonamides was successfully performed. The resulting sulfinimides were not isolated and instead were believed to go through an all-heteroatom Wittig-equivalent process to eventually afford aryl[4,5]isothiazoles in high yields.