Ultrastructural Changes Due to Toxaphene Insecticide

The deleterious effects of agricultural insecticides on non-target organisms have been under investigation for a number of years. Most studies have dealt with the degree of toxicity, mechanism of action, metabolism, or distribution in the biosphere. There has been comparatively little interest in morphological effects of an insecticide at its site of entry. Toxaphene, a general-purpose organochlorine insecticide that is widely and heavily applied in the U.S. is quite toxic to fish. It can be absorbed via the gills or the gut. This study examined the effects of Toxaphene on the absorptive cells of the anterior intestinal bulb in goldfish (Carassius auratus). These cells are involved in the uptake of dietary lipids; since Toxaphene is lipid-soluble, this was considered the likeliest region of the digestive tract to exhibit damage due to its presence.</jats:p

Ultrastructure of Baboon Zygotes Produced By Microinjection of Spermatozoa

Five baboons were treated during seven menstrual cycles with 5.0 mg of FSH-P for five days, starting on either day 3 or day 5 of the cycle. On day 5 of the treatment, the ovaries were examined by laparoscopy to evaluate follicular development. All animals exhibited multiple preovulatory follicles and at that time 100 mg GnRH was administered intramuscularly to induce LH release. Between 24 and 30 hours after injection of GnRH, laparoscopic follicular aspiration was used to collect oocytes. These were matured in vitro (determined by extrusion of the first polar body) and fertilized by microinjection with frozen-thawed baboon spermatozoa. Male and female pronuclei were observed in 32% of the resulting zygotes within 24 hours. These zygotes were compared to a zygote in the same stage that had been fertilized in vivo and obtained by laparoscopy and flushing of the oviduct.</jats:p

Quantitative nephelometric determination of Haemophilus influenzae antigen in body fluids

Nephelometry, an immunological technique widely used for the quantification of blood proteins, was adapted to provide a quantitative method of detecting Haemophilus influenzae capsular antigen in body fluids. Using specific antiserum directed against H. influenzae capsular antigen, samples of serum, cerebrospinal fluid, urine, and joint fluid from 38 cases of H. influenzae infections were analyzed. The results were compared for reliability to counterimmunoelectrophoresis, a widely used diagnostic tool. The nephelometric technique has the same advantages of speed and specificity as counterimmunoelectrophoresis and provides the clinician and researcher with a quantitative method that is as reliable as the qualitative counterimmunoelectrophoresis procedure. The method allowed directly quantitative readouts on patient specimens, with no necessity for serial dilutions or densitometric readings.</jats:p

Ruthenium Red Enhancement of Surface Complex Components of Isolated and in Situ Cardiac Myocytes of Syrian Hamsters

Fibrils of widely differing sizes have been reported in association with the sarcolemma of cardiac myocytes in situ. Elements of this surface complex include 25-50 nm-thick striated collagen fibrils, 8-10 nm-thick unbanded fibrils (UFs), and fine 4-6 nm-thick glycocalyceal fibrils. In addition, glycosaminoglycans (GAGs) have been found associated with the surface complex. SEM examination of the surface of mechanically disaggregated myocytes revealed longitudinally-oriented cable-like fibers bridging the Z-band depressions. These cables are believed to correspond to the UFs seen in TEM preparations. We are currently studying the surface complex of isolated cardiac myocytes in an attempt to clarify its role in myocardial mechanics. In order to define the elements of the surface complex of these cells, and to examine their relationships to one another, we have applied the ruthenium red (RR) method of Luft.</jats:p

Apoptosis in the myocardium of the adult dromedary camel: Ultrastructural characterization

No Abstract

Stimulation of non-opsonic phagocytosis in avian respiratory phagocytes

Avian respiratory disease costs the U. S. poultry industry millions of dollars per year in lost production. The avian respiratory system, while similar in many ways, differs from that of mammals anatomically, physiologically, and in its response to invasion by infectious agents. One of the least understood components is the variety of cell types collectively referred to as avian respiratory phagocytes (ARP), the first line of defense against invasion. The resident ARP population is normally very low, but numbers increase in response to certain stimuli. We undertook a study to quantify the extent of ARP influx and the degree of increase in phagocytic activity in response to the presence of non-pathogenic Pasteurella multocida. Chickens were stimulated by intratracheal inoculation of P. multocida, and the ARP's collected by lavage of the lungs and air sacs. Control birds were inoculated with vehicle carrying no P. multocida, and then lavaged.</jats:p

A Scanning Electron Microscope Study of Mature Aspergillus Flavus Sclerotia

Raw or processed foodstuffs contaminated with the mycotoxin-producing fungus Aspergillus flavus Link ex Fries may present serious health hazards to humans and animals. Practices aimed at reducing A. flavus contamination of food and feed are being developed. These attempts would be facilitated by an understanding of the life cycle and the survival of the fungus. The formation of sclerotia in culture or on plant tissue by several isolates of A. flavus prompted this morphological study. Sclerotia are broadly defined as aggregations of vegetative hyphae of determinate growth that are capable of surviving adverse environmental conditions. To our knowledge, this is the first SEM study of the sclerotia of A. flavus.</jats:p