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The first use of a new irrigation/aspiration tip resulted in a posterior capsular rupture. Scanning electron microscopy of the tip revealed burrs on the aspiration portion of the tip, as well as poor finishing around the irrigation ports.
A rat model has been developed to compare relative morphological changes in the nasal mucosa after exposure to potential membrane permeation enhancers. Scanning electron microscopy was used to characterize gross structural and specific cellular changes following exposure. Micrographs of the rat nasal mucosa were scored in four categories: (1) mucosal surface integrity, (2) ciliary morphology, (3) mucus/extracellular debris, and (4) presence of red blood cells. The order of increasing morphological damage resulting from a 5-min exposure to each surfactant was 0.5% Solulan C-24 congruent to 0.5% Solulan C-24/0.5% sodium tauro-24,25-dihydrofusidate (STDHF) less than 0.5% STDHF less than 1.0% STDHF much less than 1.0% Laureth-9 less than 1.0% sodium taurodeoxycholate congruent to 1.0% sodium deoxycholate. The changes observed in the mucosal morphology after exposure to the various surfactants are in general agreement with data in the literature. This model is able to compare rapidly the relative morphological effects on the mucosal membrane of different nasal formulations.
BACKGROUND AND STUDY AIMS: Gastric mucosa may have several tiny patterns in portal hypertension. In this prospective study, we used magnifying endoscopy and scanning electron microscopy (SEM) to better characterize the morphology of gastric mucosa in patients with cirrhosis, and we evaluated the diagnostic accuracy of magnifying endoscopy. PATIENTS AND METHODS: Videotapes of gastric mucosal patterns from 39 cirrhotic patients and 20 control patients were blindly evaluated by the same observer using magnifying endoscopy (magnification x 25) and conventional endoscopy. SEM was performed in 12 other patients. The basic anatomical entities of the gastric architecture on conventional endoscopy were the gastric area in control patients and the mosaic pattern in patients with cirrhosis. RESULTS: With regard to the prevalence of endoscopic patterns in the antrum, the mosaic pattern was more frequent in cirrhotic patients. In the body, the mosaic pattern, white spots, and red marks were significantly more frequent in cirrhotic patients, whereas gastric areas were more frequent in control patients. Concerning the contributions of the techniques, significantly more gastric areas were identified by magnifying endoscopy than by conventional endoscopy. However, in multivariate analysis, only conventional endoscopy with esophageal varices had significant independent diagnostic accuracy for cirrhosis, and magnifying endoscopy of mucosal signs did not add any significant information. SEM did not improve discrimination between control and cirrhotic patients. CONCLUSIONS: Magnifying endoscopy provides more details of the mucosa, thus improving the delineation of gastric mucosal morphology. However, magnifying endoscopy has little clinical value in cirrhosis since it does not improve on the accuracy of conventional endoscopy for the diagnosis of cirrhosis.
In order to evaluate the effects of potassium cristalloid cardioplegic solutions (CPS) on the endothelial morphology, human saphenous veins were studied by scanning electron microscopy after exposure to three CPS named MKP (magnesium-potassium-procaine cardioplegia), LK (low-potassium cardioplegia), and HKA (high-potassium-albumin cardioplegia) and to their main components. Vein rings, selected from the saphenous veins sampled for graft harvesting in 63 patients undergoing aorto-coronary bypass surgery, were exposed for 30, 60, and 120 minutes to the following buffered solutions: Krebs bicarbonate (as control); MKP cardioplegia; KCl (16.0 mmol/L); MgCl2(2).6H2O (16.0 mmol/L); Procaine (0.05 mmol/L); NaCl (92.5 mmol/L); LK cardioplegia; KCl (10.0 mmol/L); Mannitol (74.3 mmol/L); Glucose (27.7 mmol/L); HKA cardioplegia; KCl (30 mmol/L). Severe endothelial lesions, consisting of diffuse disendothelialization and diffuse signs of endothelial suffering, were induced by KCl (30 and 16 mmol/L) after 60-120 min, and by MKP cardioplegia and KCl (10 mmol/L) after 120 min. Moderate endothelial lesions, characterised by diffuse endothelial surface changes and focal cellular loss, were induced by KCl (30 and 16 mmol/L) after 30 min, MKP cardioplegia and KCl (10 mmol) 30-60 min, LK cardioplegia, HKA cardioplegia, and MgCl2.6H2O after 120 min. Slight endothelial lesions, consisting of diffuse endothelial bulging, or absence of significant endothelial changes, were found in samples otherwise treated. Our findings showed a significant damaging effect of CPS on the human saphenous vein endothelium in-vitro. The endothelial lesions seemed related to the presence of potassium and magnesium, and to prolongation of the time of exposure to the cardioplegic solutions.(ABSTRACT TRUNCATED AT 250 WORDS)
Impression cytology specimens of the conjunctiva can be examined by scanning electron microscopy. If a cellulose-acetate filter is pressed onto the conjunctiva, the microvilli-bearing epithelium becomes so firmly attached to the fine meshwork of the filter that the most superficial conjunctival cell layers adhere to the filter. When the filter is removed intercellular connections are destroyed without any damage to the cell membranes being detectable in the SEM image. Since the surface of the corneal epithelium is spread out on the filter and is firmly attached to it the lateral bond between the cells is preserved. Shrinkage is minimal. The posterior surface of the epithelial cells, facing the observer, consists of smooth, porous cell membranes. The nuclei of many cells are clearly distinguishable. Since it can be directly compared with light-microscopic specimens, the SEM image can help provide answers to morphological and pathological questions, and may represent a useful diagnostic aid.
Evidence is presented that cytoskeletal structures (actin filaments, intermediate filaments, and microtubules) can be resolved by scanning electron microscopy after osmium impregnation of biological material, using thiocarbohydrazide as a ligand, followed by critical-point drying. These different classes of filaments or tubules can be identified both as purified protein polymers and as structured organelles within cryofractured or detergent-extracted cells.
Biopsies of healthy looking urothelium from 61 patients with transitional cell carcinoma (TCC) of bladder were examined by scanning electron microscopy (SEM) and light microscopy. A proportion (40%) showed abnormal features on SEM, in particular pleomorphic microvilli (PMV) in at least one area. SEM appearances were graded into four categories depending upon divergence from normal. Patients were followed up at cystoscopy and one year later a strong correlation was noted between original abnormal SEM appearances and subsequent tumour recurrence. These early results suggest that SEM could be helpful in the diagnosis, assessment, and clinical management of the unstable urothelium.
The ultrastructure of glycocalyx and ciliary interconnections of the human vestibular end organs was investigated in a three-dimensional way by using scanning electron microscopy. The plasma membrane showed a rather rough appearance, which was most prominent in the ciliary membrane of sensory cells. Ciliary interconnections emerged from the plasma membrane and tightly connected neighbouring cilia. The tip links stretched from the tips of the stereocilia to their taller neighbours. These tip links were arranged in the direction of the kinocilium. These findings indicate that the ciliary interconnections may keep the cilia arranged in a bundle and the tip links may be involved in the sensory cell transduction system.
Three dimensional vascular architecture in the omasal laminae of sheep was studied by scanning electron microscopy of corrosion casts. The omasal laminae were equipped with well-developed subepithelial capillary network with various capillary loops and inter-papillar undulations. The capillary loops were more highly developed in the omasal papillae than in the inter-papillar space and more in the oral region than in the aboral. The capillary loops were inconspicuous in the inter-papillar space of the middle and aboral regions and in the omasal papillae of the aboral region. On the other hand, the inter-papillar undulation of the capillary network was more conspicuous in the aboral region than in the other regions of the omasal mucosa. These findings may indicate a regional diversity in the function of the omasal laminae.
The addition of ethidium bromide during the last 2.5-3 h of lymphocyte culturing restricted chromosome contraction and preserved the banding structure in scanning electron microscopy. Treatment of the chromosomes with trypsin and use of impregnation with osmium tetroxide and thiocarbohydrazide resulted in a structural preservation of high resolution quality.
Various methods of preparation were tested and modified in order to establish a proper method of preparing normal and pathological human erythrocytes for scanning electron microscopy. Morphological changes after various preparation techniques, such as echinocytosis, spherocytosis, elliptocytosis and knizocytosis were studied and evaluated statistically. The best method, so far obtained to preserve 99% of normal erythrocytes as biconcave discocytes, was that of venous blood without anticoagulants or acid-citrate-dextrose, washed with physiological saline at 37 degrees C, fixed in 0.75% glutaraldehyde in 0.1 M phosphate buffer, pH 7.3 (318 mosmol), postfixed in 1% osmium tetroxide, dehydrated with graded ethanol and amyl acetate, dried with critical point drying method, and coated with carbon and gold.
The myoepithelial cells of the human ceruminous apocrine gland were observed with transmission and scanning electron microscopes. The myoepithelial cells are long fibrous cells about 100-150 mum in length and 3-5 mum in width. They are arranged in parallel with each other, and their long axes are parallel to that of the secretory tubule itself. The tips of cells are often sharply pointed and their lateral tapering surface may be contiguous with adjacent cells forming a side-by-side contact, while other cells may have a blunt tip which is conjuncted with a similar tip of the next cell forming an end-to-end junction. The myoepithelial cells are joined to each other by desmosomes and there are also desmosomes at their junction with secretory cells. The outer surface of the cell abutting on the basal lamina has some exaggerated densities which are undoubtedly identical to the hemidesmosomes of epidermal cells. There are well developed foldings in the plasma membrane of the secretory cells, but the surface of the myoepithelial cells has very few foldings and projections. The relative shortage of intercellular attachment devices between the secretory and myeopithelial cells makes it easy to peel off the secretory cells to disclose the myoepithelium, a useful feature of scanning electron microscopy. The nucleus-containing part of the cell protrudes slightly upward and invades the secretory epithelium. The cytoplasmic rim surrounding the nucleus contains a small Golgi apparatus and some other organelles. The cytoplasm of the basal half of the cell contains closely packed myofilaments running parallel to the long axis of the cell. There is no definite arrangement of thin and thick myofilaments. Microtubules which often occur in pairs are arranged parallel to the myofilaments.
The surface patterns of the chicken hen oviductal mucosa apposing an ovum were examined by scanning electron microscopy. The distended infundibular mucosa consisted of folds that were separated by interfold spaces of similar width and longitudinal orientation. The epithelium, which lined the base of the interfold spaces, was nonciliated and appeared to correspond to the glandular grooves, which are the sites of sperm storage in the infundibulum. The presence of an ovum in the magnum or isthmus resulted in the flattening of the mucosal folds and occlusion of the oviductal lumen. The uterine mucosa was slightly compressed when apposed to an egg and wide interfold spaces were evident.
The lysis of a fibrin clot by sheets of endothelium one cell thick was examined by scanning electron microscopy. The unlysed fibrin film appeared as a densely matted surface, without interstices. Commencing lysis appeared as parallel ovals in which the dense matting was altered to show many strands of fibrin criss-crossing the lytic "window" with many interstices. The wall of the lytic crater surrounding the sheets of endothelium revealed a network of fibrin strands. There was condensation of the fibrin at the edge of the hole at the external surface. The floor of the crater contained sheets of endothelium which were recognized by the shape and size of the nuclei. Flocculent masses of precipitate were present on the endothelial cells in the floor of the crater and occasionally within the lysed ovals at the edge. These may be fibrin degradation products.
Surface structures of males and females of Setaria labiatopapillosa were studied by means of scanning electron microscopy at high magnification. It was found that the surface of buccal cavity, lateral appendages, vulva, anus and cloaca differs from the remaining cuticle. The shape of internal and external mouth papillae, amphids, deirids, postdeirid and phasmidial pore was studied. On the surface of the postdeirid are four small papillae arranged in a typical manner around the depression from which projects a needle-like formation. The ventral bands are formed by fine longitudinal parallel folds of the cuticle. Some anomalies in the localization of postcloacal papillae were observed.
The surface morphology of the trypanorhynchan pleurocercoid larva of Otobothrium sp. was studied by scanning electron microscopy. Some morphological features reported here are unique; these include the presence of three morphologically different microtriche like structures: wide tridigitate and narrow cylindrical elongate structures on the adhesive surface and the margin of the bothridia respectively, and short knob-like on the body of the larva. The topography of the scolex was also described.
Extracted teeth due to consequence of chronic periodontitis of adult are fractured and the apical cementum to junction epithelium is examined under S.E.M. (scanning electron microscopy) being found bacterias forms inside niches of the apical cementum.
A patient who repeatedly produced urinary calculi, had consumed about 3 g of cristobalite (SiO2) per day for many years. Investigations using scanning electron microscopy revealed minute particles containing silicon in the core of the stone as well as in urine sediment. A mechanism similar to that proposed for the effect of silicon-containing drugs against gastric ulcer, may play a role in this formation of silicon-containing urinary stones.