The ultrathin sections
were prepared according the previous report followed by observation with transmission electron microscopy (HITACHI-H7650, Tokyo, Japan) .
without lead staining were observed using Jeol 1010 electron microscope.
of white matter from spinal cords for the control (A) and sham (B) groups, showing myelinated (red arrows) axons with normal axoplasm (stars).
were prepared and treated as described in the Materials and Methods section.
To substantiate this finding, we examined ultrathin sections
from injured and uninjured optic nerves and compared their morphological features with those of the damaged nerves derived from the treated group.
The total number of synapses within an unbiased counting frame of a known area ([A.sub.frame]) was counted(1620 [micro][m.sup.2] per brain at 50,000x for the ultrathin sections
Electron micrographs were taken on ultrathin sections
(70 nm) with a Zeiss EM9000 electron microscope (Carl Zeiss, Oberkochen, West Germany).
Semithin and ultrathin sections
were made on ultra microtome "Reichert--Jung" (Reichert, Austria).
Initially, semithin 0.5 [micro]m sections were made on Reichert-Jung (Ultracut E) ultramicrotome with a glass knife, for the localization of fungal structures of interest in a light microscope and for orientation of the ultrathin sections
. The semithin sections were collected with a gold ring and placed on glass slides, dried in a metal plate at ~60[degrees]C, covered with toluidine blue stain (1g toluidine blue, 1g sodium borate and 100ml of water, filtered through a Millipore 0.2[micro]m), heated on a metal plate until formation of a golden border, washed with distilled water, dried on a hot plate and visualized by light microscopy.
For transmission electron microscopy (TEM), the hand sections taken for light microscopy were curt into smaller pieces, dehydrated in an acetone series, and embedded in Spurr's low viscosity resin.(26) Ultrathin sections
were cut with an ultramicrotome using a diamond knife, stained with 1% potassium permanganate (prepared in 0.1% sodium citrate), and then examined with a Philips 300 TEM.
Electron microscopy of negative-stained grids prepared at HPA and NCID laboratories from pustular material showed orthopoxvirus particles, and examination of ultrathin sections
prepared from infected Vero cell cultures at HPA found classic orthopox intracytoplasmic virus factories and particle maturation sites (Figure 1C, D).
On ultrathin sections
, 12 fields, corresponding to an area of 1,820 [micro][m.sup.2] each, were systematically subsampled and investigated for the presence and localization of Ti[O.sub.2] particles in a LEO 912 transmission electron microscope (LEO, Oberkochen, Germany) equipped with an in-column energy filter allowing energy dispersion for element specific contrast.