Multimodal label-free imaging of murine hepatocellular carcinoma with a subcellular resolution.

We demonstrate label-free imaging of genetically induced hepatocellular carcinoma (HCC) in a murine model provided by two- and three-photon fluorescence microscopy of endogenous fluorophores excited at the central wavelengths of 790, 980 and 1250 nm and reinforced by second and third harmonic generation microscopy. We show, that autofluorescence imaging presents abundant information about cell arrangement and lipid accumulation in hepatocytes and hepatic stellate cells (HSCs), harmonics generation microscopy provides a versatile tool for fibrogenesis and steatosis study. Multimodal images may be performed by a single ultrafast laser source at 1250 nm falling in tissue transparency window.

Modeling of the cerebral blood circulation in a capillary network accounting for the influence of the endothelial surface layer.

Background And Objective: The paper describes a mathematical model of blood flow in capillaries with accounting for the endothelial surface layer (ESL).

Method: The influence of ESL is modeled by a boundary layer with zero flow velocity. Finite element modeling and an analytical approach based on the homogenization of the core region of blood flow occupied by erythrocytes are developed to describe the resistance of a capillary.

A rapid room-temperature cloud point extraction for spectrophotometric determination of Copper (II) with 6,7-dihydroxy-2,4-diphenylbenzopyrylium chloride.

The conditions for the surfactant rich phase of Triton X-100 formation and the extraction of Copper (II) as a complex with 6,7-dihydroxy-2,4-diphenylbenzopyrylium chloride at room temperature have been optimized. It was shown that the sodium salt of p-toluic acid can be used as a chemical initiator of cloud point extraction. The optimal conditions for room temperature cloud point extraction were found to be: pH 5.

Multimodal nonlinear-optical imaging of nucleoli.

Multimodal nonlinear microscopy combining third-harmonic generation (THG) with two- and three-photon-excited fluorescence (2PEF and 3PEF) is shown to provide a powerful resource for high-fidelity imaging of nucleoli and nucleolar proteins. We demonstrate that, with a suitably tailored genetically encoded fluorescent stain, the 2PEF/3PEF readout from specific nucleolar proteins can be reliably detected against the extranucleolar 2PEF/3PEF signal, enabling high-contrast imaging of the key nucleolar ribosome biogenesis components, such as fibrillarin. THG is shown to provide a versatile readout for unstained nucleolus imaging in a vast class of biological systems as different as neurons in brain slices and cultured HeLa cells.

Dispersive Liquid-Liquid Semi-Microextraction of Сu(II) with 6,7-dihydroxy-2,4-diphenylbenzopyrylium Chloride for its Spectrophotometric Determination.

A novel dispersive liquid-liquid semi-microextraction (DLLsME) procedure for copper(II) preconcentration is proposed. The system containing copper(II) and 6,7-dihydroxy-2,4-diphenylbenzopyrylium chloride (DHDPhB), after addition a mixture of chloroform and methanol becomes cloudy and the formation of the organic phase was observed immediately. The optimal conditions of DLLsME were found to be: pH 5, absorption band maximum was 570 nm, 1 cm3 of 1×10-3 mol/dm3ofDHDPhB, and mixed extractant containing 1 cm3 of chloroform and 1 cm3 of methanol.