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The parasympathetic cardiac ganglion in the mudpuppy, N. maculosus , contains postganglionic nerve cells and intrinsic neurons, many of which are small intensely fluorescent (SIF) cells. Several bioactive substances have been localized in the intrinsic nerve cells which may have integrative effects at synapses within the ganglion. Ganglionic intrinsic neurons can be identified electron microscopically by the presence of numerous cytoplasmic granular vesicles 80–120 nm in diameter. Throughout the ganglion there are bundles of unmyelinated fibers some of which are filled with granular and agranular vesicles and axosomatic terminals with similar vesicles synapsing on principal parasympathetic nerve cells. To understand the aminergic contribution to ganglionic synaptic circuitry the chromaffin reaction was used. The intrinsic neurons (i.e., SIF cells) were readily identified by their characteristic intracellular granule population. All intrinsic nerve cells identified showed granules which were positively labelled by the chromaffin reaction. Granular vesicles in synaptic profiles on principal cells (P cells) were also labelled indicating a direct aminergic synaptic innervation to these cells. The cell bodies of intrinsic neurons, ensheathed with supportive glial-like cellular processes, rarely received synapses. Elemental microanalysis was used to verify the chromium content of the electron dense product within the granular vesicles. These studies demonstrated direct aminergic synaptic input to at least a subpopulation of principal parasympathetic cells in the cardiac ganglion of mudpuppy.

A technique was developed to prepare archaeological fiber cross sections for electron microscopic examination and x-ray analysis. Use of this new method allows chemical and morphological information to be obtained from the interior of a single fiber or yarn. Fibers are fractured while frozen and then freeze dried. Following mounting and carbon coating, fibers are examined by scanning and backscatter electron microscopy and then analyzed by using energy-dispersive spectrometry. Elemental distribution is mapped by using image-processing software. In this report, the described technique is employed in the examination of ancient fibers from three different long-term storage environments (moist buried, dry buried, museum stored). Data obtained by examining the interior of fibers such as these provide insight into the conditions of a fiber's growth, the treatments applied during the fiber's processing and use, and the conditions in which the fiber was stored.

Cadmium and metallothionein (MT) levels were measured in lungs derived from Lewis rats exposed 0, 5, 10, 15, 20, 24, or 30 times to a Cd acetate aerosol (1.6 mg/m3). Cd burden rose from 2.21 micrograms in control lungs to 42.55 micrograms in lungs of animals exposed 30 times to the Cd aerosol. Pulmonary MT, expressed as nmoles Cd-thionein, paralleled Cd retention. Levels increased from 7.5 nmol in control animals to a value of 340.5 nmol in animals exposed 30 times to Cd. Energy dispersive X-ray microanalysis and the laser micro-probe analyzer were used to localize Cd within the lung. Lung tissue was prepared by a variety of chemical and physical fixation procedures. Cd localization proved unsuccessful by these techniques, presumably because the cellular Cd levels were below the limits of detectability. Using a immunohistochemical procedure which employed an antibody to MT, pulmonary MT was found in alveolar epithelial cells, fibroblasts, and lymphocytes. The MT was restricted to the nuclei of these cells.

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.