Sliding microtome

Three UF resins with different degrees of condensation together with extender and hardener were used as adhesive mixes and were apphed onto one of the surfaces to be bonded by hot pressing parallel to the grain direction, with Safranin added as a coloring agent. Microtome slides (20 pm thick) were cut from each joint sample, showing the bondline and the two adherends with the resin penetrated in radial direction. The depth of adhesive penetration was determined by epi-fluorescence microscopy. 

Individual depths of penetration ( jm) were determined from each photomicrograph of the microtome slide at 45 positions within the 1400 pm width of the bondline. The depth of penetration here is defined as the sum of the distances the resin could penetrate into the two plies starting from the bondUne. No separate evaluations for the two plies was done during the evaluation of AP and FIR, even though there might be some small difference in the individual penetrations between the ply where the adhesive mix had been applied and the ply without application of adhesive mix. Each of the three AP results (one for each resin type) as shown below is the result of nearly 7000 individual measurements. 

Several microtome slides were also examined with fluorescence confocal laser scanning microscopy (CLSM). Scanning electron microscopy (JEOL JSM-... 

Prepare duplicate or triplicate 2- to 3-mm-thick sections of the sample on a microscope slide. For best results, allow sample to solidify directly on the slide so that the surface is sufficiently smooth for imaging. If starting with solidified products, prepare section with a razor blade or a microtome, if possible, for optimal smoothness. 

Phase contrast-Thin sections (100-200 nm) in thickness (and having refractive indices which differ by approximately. 005) are supported on glass slides and examined "as is" or with oil to remove microtoming artifacts, e.g., determination of the number of layers in coextruded films, dispersion of fillers, and polymer domain size. (Figures 2 and 3)... 

Cut 4-pjn-thick sections with a microtome and float them on a water bath kept at room temperature so as to stretch the sections. An ordinary glass slide is used to transfer the sections onto another water bath kept at 58°C to further stretch the sections. Lift them by the SuperFrost slides, thus mounting them in the process. The sections are allowed to dry in an upright position in a slide holder at a temperature of <30°C. When the slide holder is full, it is transferred to a conventional oven. 

Human brain tissues, for example, are fixed postmortem with 10% formalin for 24-48 hr, dehydrated, and embedded in paraffin. Sections, cut with a rotary microtome, are mounted on coated glass slides. The sections are rinsed three times for 5 min each with 0.1 M sodium phosphate buffer (pH 7.4) and then transferred to 10-15 mM sodium citrate... 

Thin samples can be sliced from an appropriately mounted bulk sample. Smaller samples can be imbedded in a wax block. Automated sliding microtomes can be used for slicing. Thin samples are hard to handle and may curl. A microcompression cell can be used to hold the samples. Unfortunately, microtoming can introduce arifacts into the samples by tearing and orientation. 

Carefully extracted samples of peat were slowly dehydrated in a series of alcohol solutions and then embedded in paraffin. After embedding, thin-sections (15 microns in thickness) were cut from these samples with a sliding microtome and mounted in Canada Balsam. Details of the procedure for the embedding and sectioning of peats have previously been described by Cohen.(2,3). 

The sample preparation procedures for the direct analysis of small molecules in tissue have been described by several papers [120-124], Tissues (brain, heart, lung, kidney, liver, etc.), were immediately frozen and stored at -80 °C after harvest. The frozen tissues were subsequently cut into serial 10-20 pm thick section which was typically prepared by cryosectioning on a microtome at a temperature of -20 °C. The adjacent sections were gently mounted onto a conductive surface, MALDI imaging target plate or glass slides. These plates were desiccated under low vacuum for a short period of time until dry, then robotically or manually coated with the... 

For optical microscopy, hairy root specimens were fixed with 3 % formaldehyde in 50 mol m phosphate buffer (pH 6.8) for 1 h at ambient temperature. Cross-sections of the specimen were prepared using a sliding microtome equipped with a specimen-freezing stage. The sections were examined with microscopes under conventional or fluorescent light (excitation wavelengths of 520-550 nm and emission wavelength of >580 nm). 

Handwritten slides present an additional set of potential identification pitfalls. If the slides are written in batch (pre-writing the slides based on predetermined protocols with expected numbers of slides to be cut for that case) the same potential sequencing problem exists as discussed previously. In situations where slides are written at the microtome when the paraffin block is in the histologist s hand, it is imperative that the no-more-than-one-at-a-time rule come into play again. Slides are only written when the tissue has been sectioned and is picked up on the slide, thereby eliminating the risk of selecting a different slide than that assigned to that block. 

Sectioning in Paraffine or Celloidin.—When it is necessary to study the microscopic structure of very delicate plant parts, superior results can generally be obtained by imbedding the material in paraffine or ceUoidin, which is subsequently hardened, and sectioned by means of a sliding or rotary microtome. 

Microtomes are instruments employed to facilitate the cutting of sections of organic tissues. The three most commonly used types are the hand, sliding and rotary microtomes. 

Sliding Microtome.—This type of microtome (see Fig. 9) is adapted for cutting all kinds of sections. It consists of an iron supporting fame of horizontal and upright portions. The horizontal base rests on the table and is hollowed out to accommodate a drip pan that can readily be removed and cleaned. 

Fig. 9.—A sliding microtome. Blade (a) lever (6). From McJunkin.)...

Clamp the block in the sliding microtome and set the knife obliquely so that the sections can be cut with a long sliding stroke. Keep the knife and top of the block wet with the alcohol-glycerin mixture and as soon as the sections are cut, sweep them with a camels hair pencil into a dish of 70 per cent, alcohol. The sections can be attached to a slide by placing the slide in a closed chamber over ether. The ether vapor dissolves the celloidin and causes the sections to adhere to the slide. 

The green hairy roots cultured in the light for 3 weeks were used for the fluorescent microscopy and transmission electron microscopy (TEM). For the fluorescent microscopy, frozen sections (15 pm in thickness) were prepared using microtome cryostat (HM 500 OM, Microme, Heidelberg, Germany) and sealed with 50% glycerol on glass slides. Localization of chloroplasts was observed by fluorescent microscopy (VANOX AH-3, Olympus). 

Microtome cut sections are washed thoroughly with phosphate buffer saline (pH 7.4), dried and fixed on slides using Fluor Mounting medium. 

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