Biomedical subjects
Publications and source records attributed to A Kennedy.
A woman who had a large primary malignant melanoma of the oesophagus, with evidence of submucosal invasion and several local metastases, underwent resection two years after the onset of retrosternal pain and has survived for 12 years with no recurrence.
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An indirect immunoalkaline phosphatase (IAP) technique was used to evaluate the glomerular deposition of immunoglobulins, C3, C1q and fibrinogen. In 80 renal biopsy specimens the results obtained using this technique were compared with those obtained by direct immunofluorescence to see if it could be used as a viable alternative. The IAP technique was straightforward to perform, it yielded quick results, and was highly reproducible, provided that a standardised short fixation period of two and a half hours was used. For the detection of immunoglobulin deposits, the IAP results correlated well with those of immunofluorescence. Despite poorer performance in identifying complement components and fibrinogen it could, within certain limits, provide an adequate diagnostic alternative to immunofluorescence. Each technique gave false negative results, those of immunofluorescence being related to its failure to identify mesangial deposition of IgA in two cases where its distribution seemed to be focal, and those of IAP to a failure to detect linear deposition of IgG in all three cases of anti-glomerular basement membrane disease.
To investigate the effects of extracellular matrix components on cellular function, we cultured several types of ocular cells on substrates composed of extracellular matrix materials that were layered on culture dishes either as dried films or as gels. We measured cellular proliferation on these substrates and on a series of gels composed of varying proportions of rat tail tendon type I collagen and Matrigel, a commercially available extract of a basement membrane-producing murine tumor. In addition, we studied the biosynthesis of collagens and of proteoglycans by these cultured cells using [3H]-L-proline and [35S]-sulfate. The proliferative abilities of the various types of ocular cells on the dried film substrates, on uncoated plastic culture vessels, and on pure type I collagen gel, were similar. However, proliferation of ocular cells cultured on gels composed of greater than or equal to 90% Matrigel was markedly reduced. There was little or no inhibition of growth of two types of non-ocular cells: rat C6 astrocytoma cells, and human dermal fibroblasts. Histologic studies showed that the ocular cells tested often formed long strands and capillary-like tubes, and tended to "burrow" beneath the surface of substrates containing high percentages of Matrigel. Fibroblasts infrequently formed tubes, and exhibited the burrowing property also on gels containing primarily type I collagen, while C6 cells showed neither of these behaviors on any of the matrices tested. The elution pattern of newly synthesized [3H]-labeled and [35S]-labeled macromolecules produced by all of the cultured cell types, and detected by Sepharose CL-4B chromatography in the medium and in the cell layer plus matrix fractions did not vary following culture on the different substrates. Approximately twofold more of the newly synthesized collagens and proteoglycans were deposited in the cell layer plus matrix, and proportionately less appeared in the medium, when cells were cultured on type I collagen gels and on Matrigel than on the dried film substrates. These experiments demonstrate the influence of the extracellular matrix on several aspects of cell behavior, and provide further evidence that modification of the composition of the extracellular matrix may be an important determinant of normal or pathological cell function.
The pelvic pain syndrome is a major cause of morbidity in young multiparous women. Psychotherapeutic, medical and surgical treatments are available and therefore accurate diagnosis is important. This article reviews the imaging methods available for the diagnosis of ovarian varices and pelvic venous congestion.
Cholesterol embolism is an unusual but serious complication of intra-arterial procedures such as arteriography and angioplasty. The pathological findings in four cases confirm that this syndrome is due to disseminated micro-emboli composed mainly of cholesterol crystals and that these originate from atheromatous plaques in the aorta which may be traumatized by the catheter used in the intra-arterial procedure. However, angiography is not the sole precipitating cause of this syndrome but is an exacerbating event in a pre-existing process.
In a 12-month survey on the causes and frequency of hypoglycaemia presenting to an inner-city accident and emergency department, a total of 86 cases were recorded. A missed meal and/or alcohol ingestion accounted for most of the precipitating causes, being 52% and 21% respectively. As 49% of subjects presented with major clinical manifestations of hypoglycaemia (fit or coma), greater emphasis is required in the instruction on regularity of meal and caution with alcohol in high-risk groups such as the diabetic and also in non-diabetic groups.
The quality of microscopic image of cryostat sections that had been subjected to microwave assisted fixation was compared with that resulting from conventional air drying of the sections. The role of microwaves in producing rapid special stains on cryostat sections was also assessed. Methods used permitted stains such as periodic acid Schiff, alcian blue, Gordon and Sweets's reticulin, Masson Fontana, Elastica, Prussian blue and Van Gieson to be performed within three minutes of cutting a cryostat section. The cytological detail of nuclei was much clearer using the microwave technique, allowing more accurate determination of cell type. The microwave oven seems to have major potential in improving the diagnostic accuracy of surgical frozen sections.
We have examined the feasibility of combining immunocytochemistry with argyrophilic staining of nucleolar organizer regions (AgNORs) on a single preparation. The combined technique gave positive results on fixed tissues, with immunoalkaline phosphatase methods providing better contrast. On frozen sections, there were problems with adhesion and with immunostaining. Delayed fixation did not affect AgNOR staining, suggesting that the technique may be applied to autopsy tissue. Trypsinisation of sections did not alter the count of silver stained granules.
We have described the clinical presentation of the commonest syndromes associated with hormone production by functioning pancreatic tumors. The role of the radiologist in tumor localization, staging, and treatment is discussed and the various imaging methods employed are examined individually. The problems of reviewing the world literature on such rare lesions are discussed and a tentative diagnostic algorithm is suggested.
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We have derived a cell line from an epiretinal membrane excised surgically from a premature female infant born at a gestational age of 25 weeks, and who developed stage 5 retinopathy of prematurity. The cell line, which in early passages appeared immunocytochemically to contain cells with both neuronal and glial characteristics, has been maintained in culture for 14 months at the time this manuscript was submitted, and has survived 20 passages. The cells have a diploid, human karyotype, with most cells possessing 46 normal appearing chromosomes, including 44 autosomes and two X-chromosomes. Morphologically, the cell line at early passages consisted of polygonal cells and also of cells possessing long, spindly branching processes. These two cell types were cloned. Nearly 100% of the cells of both morphologic types in mixed cultures stained immunocytochemically for neuron-specific enolase (NSE), a neuronal marker, and approximately 5-10% of the cells in mixed cultures (including about 50% of the cells with the spindly morphology, that were less prevalent in mixed cultures) stained for glial fibrillary acid protein (GFAP), a glial marker. We have not performed "double-label" immunocytochemistry, but it was evident from the proportion of cells that stained with each marker that many cells must contain both GFAP and NSE. At least 50% of the cells in most of the early cultures were positive for keratin, while all were (and remain) negative for muscle actin. No cells are found that are immunocytochemically positive for factor VIII, a vascular endothelial cell marker. These cultured cells have also been studied immunocytochemically for their production of extracellular matrix substances. The cultures are immunocytochemically positive for type IV (but not type I) collagen, laminin and fibronectin. In later passages, cells of both clones lost their immunocytochemical positivity for GFAP and NSE, and all became positive for keratin. Cells of both clones also developed a similar, polygonal morphology, lacking long processes. By electron microscopy, many of the cells were seen to possess nonmotile cilia, with a 9 + 0 pattern of microtubule doublets. This cell line may be useful for studies of human retinal cell development and metabolism, and responses to pathological processes.
Cholesterol embolisation after vascular catheterisation occurred in 5 patients. It tended to be associated with difficult manipulation of the catheter within a severely diseased aorta, and a common feature is leg pain with livedo reticularis despite palpable pulses. Confusion, renal failure, and death ultimately ensue.
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