H 7000fa transmission electron microscope

Freshly dissected heart tissues (0.5×1×5 mm) were fixed with 2% glutaraldehyde overnight, washed three times with 0.2 M phosphate buffer, fixed with 1% osmium tetroxide, washed with 0.2 M phosphate buffer, and dehydrated in a series of ethanol concentrations. Specimens were immersed in Epon 812 resin/acetone (1∶1) for 30 min, then fresh Epon 812 resin for 30 min, and then embedded and incubated overnight at 70°C. The tissues were sectioned into 50-nm thick slices using an LKB-8800 ultramicrotome (LKB-Produkter AB, Bromma, Sweden). Cardiomyocyte mitochondria and sarcomeres were observed with an H-7000FA transmission electron microscope (Hitachi, Tokyo, Japan) at ×10000 magnification.

Effect of MgONFs on cellular integrity of Xoo strain GZ 0005 was determined according to the method of Li et al. [29 (link)] with some modifications. In brief, the overnight cultured bacteria were inoculated into MgONFs solution of 2 μg/ml to give a final bacterial concentration of 10⁸ CFU/ml and then the mixture was incubated on a rotary shaker (160 rpm) at 30°C for 2 h. After centrifugation at 8000 g for 10 min at 4°C, bacterial cells were washed twice with 0.1 mol/l phosphate buffered saline (PBS) solution at pH 7.2 and fixed with 2.5% (v/v) glutaraldehyde. Post-fixation was carried out in 1% (w/v) osmium tetroxide in 0.1 mol/l PBS for 1 h at room temperature followed by dehydration at 4°C for 15 min in a graded series of ethanol solutions and embedded in Epon812, a low-viscosity embedding medium. Thin sections of the specimens were cut with a diamond knife on an Ultra microtome (Super Nova; Reichert-Jung Optische Werke, Vienna, Austria) and the sections were double-stained with saturated uranyl acetate and lead citrate. The grids were examined with an H-7000FA transmission electron microscope (Hitachi, Tokyo, Japan) at an operating voltage of 75 kV.

The size and morphology were recorded by a HITACHI H-7000FA transmission electron microscope (Tokyo, Japan). FT-IR spectrum of FOQDs was measured on a Thermo Fisher Scientific Nicolet iS10 FT-IR Spectrometer (Waltham, MA, USA). Fluorescence spectra were recorded using a Hitachi F4500 fluorescent spectrophotometer (Tokyo, Japan).

To observe the morphology of BMB171 cells and its derivative strains, 4 ml of each sample was harvested by centrifugation at 17 h, with the cell pellets resuspended in 2.5% glutaraldehyde, and stored at 4°C overnight. Ultra-thin sections were finally prepared and stained as described (Craig et al., 1997 (link)). A Hitachi H-7000 FA transmission electron microscope (Hitachi, Japan) was then used for observation.

The bacteriophage p54 was purified and concentrated using cesium chloride density gradient ultracentrifugation on 35,000 rpm for 2 h at 4°C. The concentrated bacteriophage was stained with freshly prepared phosphotungstic acid solution (2%) for 3 min and spot dried on the copper grid for 2 h. The samples were examined on H-7000FA transmission electron microscope (Hitachi, Japan).