Biomedical subjects
Publications and source records attributed to E Finkelstein.
Cutaneous leishmaniasis is now seen in non-endemic areas, especially in travellers to and troops serving in the Middle East. It was a common problem among American troops returning from the Gulf war. This article presents the clinical manifestations, the laboratory findings and the treatment options for this disease.
Hypomelanosis of Ito is an uncommon syndrome where bizarre, systematized hypopigmentation is often associated with neurological and other non-cutaneous abnormalities. We report two cases, one which was associated with laryngomalacia and sudden death (in which the parents were consanguineous), and one which was associated with episodes of loss of consciousness.
Stable nitroxide radicals have been previously shown to function as superoxide dismutase (SOD)2 mimics and to protect mammalian cells against superoxide and hydrogen peroxide-mediated oxidative stress. These unique characteristics suggested that nitroxides, such as 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempol), might protect mammalian cells against ionizing radiation. Treating Chinese hamster cells under aerobic conditions with 5, 10, 50, and 100 mM Tempol 10 min prior to X-rays resulted in radiation protection factors of 1.25, 1.30, 2.1, and 2.5, respectively. However, the reduced form of Tempol afforded no protection. Tempol treatment under hypoxic conditions did not provide radioprotection. Aerobic X-ray protection by Tempol could not be attributed to the induction of intracellular hypoxia, increase in intracellular glutathione, or induction of intracellular SOD mRNA. Tempol thus represents a new class of non-thiol-containing radiation protectors, which may be useful in elucidating the mechanism(s) of radiation-induced cellular damage and may have broad applications in protecting against oxidative stress.
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Myospherulosis is a recently discovered iatrogenic disease caused by the implantation during surgery of mineral oil- or petrolatum-based products into various tissues. The condition results from the action of lipid substances on extravasated erythrocytes. The case report presented is the first detailed description of this uncommon, unique inflammatory lesion occurring in the mastoid and is the second otitic case reported in the literature. The lesion mimicked recurrent cholesteatoma 6 years following an intact canal wall mastoidectomy. As in myospherulosis of the paranasal sinuses, the symptoms and findings of otitic myospherulosis are those of the preceding disease.
The reactions of superoxide radical with persistent nitroxide spin-adducts or with stable spin-labels were studied using ESR spectrometry. Superoxide radicals were produced enzymatically using xanthine - xanthine oxidase or chemically by dissolving potassium superoxide in DMSO. Hydroxyl and methyl spin-adducts of the spin-trap DMPO were performed by sonolysis and subsequently reacted with superoxide radical. Superoxide-induced depletion of DMPO--OH obeyed second order kinetics. Contrary to previously published mechanisms, the reaction requires neither transition metal ions nor thiols. The depleted spin-adducts could not be restored by reoxidation with ferricyanide or copper +H2O2; thus, the superoxide-mediated destruction does not result in a mere one-electron reduction product. Superoxide also depletes other DMPO spin-adducts including DMPO--CH3 and DMPO--H, but not PBN--CH3. In addition, some 5-membered ring stable nitroxides are depleted by superoxide in a pseudo-zero order reaction. In studying systems which generate O2- and OH, the superoxide-induced destruction of DMPO--OH may well lead to erroneous conclusions regarding the primary radicals produced. In particular this reaction might be operative under circumstances where elevated rates of superoxide production take place, such as during oxygen consumption "burst" in phagocytosis, degranulation, or paraquat intoxication.
2-Ethyl-1-hydroxy-2,5,5-trimethyl-3-oxazolidine (OXANOH), the one-electron reduction product of the stable nitroxide radical, 2-ethyl-2,5,5-trimethyl-3-oxazolidinoxyl (OXANO), is reportedly oxidized by superoxide, and its oxidation has been proposed as a method for assaying superoxide. We find that superoxide can both reduce OXANO and oxidize OXANOH. The respective rate constants, k1 and k2, were determined using two superoxide-generating systems (xanthine oxidase/xanthine as well as ionizing radiation). OXANOH oxidation and OXANO reduction are both inhibitable by superoxide dismutase, pH-dependent (4.5-9.3), and result in a steady state distribution of [OXANO] and [OXANOH], independent of their initial concentrations, i.e. the OXANO/OXANOH couple exhibits a metal-independent superoxide dismutase-like function. Thus it provides a prototype for future development of improved low molecular weight superoxide dismutase mimics which will also function in cellular hydrophobic (aprotic) compartments such as membranes.
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Changes in surface proteins of leukocytes in bovine mammary secretions were examined during mammary involution. Leukocytes were collected from mammary secretions from involution days (ID) 1 to 36 and were labeled with biotin. Labeled proteins were separated by polyacrylamide-gel electrophoresis, transferred to nitrocellulose by protein blotting, and detected with avidin-peroxidase and color reagent. The population of leukocytes in mammary secretions changed during involution from predominantly polymorphonuclear leukocytes (PMN) at ID 1 to predominantly mononuclear leukocytes by ID 36. The gel profile of surface proteins also changed during involution, and some of those changes may have been caused by shifts in leukocyte populations. Profiles of surface proteins of leukocytes from mammary secretions containing predominantly PMN (ID 1) were different from profiles of PMN from blood. A distinctive change in the pattern of surface proteins on the leukocytes occurred between ID 1 and 3, even though the proportion of PMN did not change appreciably between those days.
A method has been developed which covalently attaches biotin to proteins on the outer surface of leukocytes. These proteins are separated by polyacrylamide gel electrophoresis and transferred to nitrocellulose by protein blotting. Labeled proteins are detected using an avidin-peroxidase conjugate and color indicator. The method has been used to identify surface proteins specific to either polymorphonuclear leukocytes or mononuclear leukocytes prepared from bovine peripheral blood. The method provides a highly sensitive, non-radioactive means of examining alterations of surface proteins on leukocytes under differing functional and physiological conditions. Cell viability is not altered by this labeling method and labeled cells can be used to examine functions of surface proteins.
We report the case of a 20-year-old woman who presented with a subconjunctival maggot. The maggot was removed and identified as the larval form of the horse bot fly (Gasterophilus spp.). The patient had been grooming infected horses in a stable prior to presentation. To our knowledge, this is the first well documented case in the ophthalmic literature of external ophthalmomyiasis caused by Gasterophilus spp.
The radiation responses at various oxygen tensions were evaluated in V79 Chinese hamster cells under conditions where their nonprotein thiols, primarily glutathione (GSH), were elevated by 2-oxothiazolidine-4-carboxylate (OTZ). OTZ, when cleaved by intracellular oxoprolinase, provides the cell with cysteine which stimulates GSH synthesis. A 2-hr pretreatment with 10 mM OTZ elevated GSH to 200% of controls. This elevation in GSH offered no protection to aerated cells; however, for O2 tensions less than or equal to 40,000 ppm modest protection was observed as evidenced by an increase in oxygen enhancement ratio. GSH elevation afforded maximal protection between 1000 and 10,000 ppm O2; however, the extent of protection was relatively small (protection factor = 1.3).
A Maltese immigrant presented with intermittent bilateral anterior uveitis for which no cause could be found. The inflammation did not respond to topical treatment and ultimately the left eye developed a hypopyon and was enucleated. Histological examination revealed granulomatous inflammation and large numbers of Mycobacterium leprae throughout the anterior segment. Occasional foci of inflammation containing Mycobacterium leprae were found in the vitreous extending to the retina at the posterior pole. These findings in the posterior segment have rarely been reported. Eye infection in Hansen's disease is frequent and delays in diagnosis are common.
A 57-year-old housewife, with controlled hypertension, presented with acute right proptosis and visual loss with external ophthalmoplegia due to spontaneous orbital haemorrhage. Vision and ocular motility were returned to normal by the rapid surgical evacuation of the blood. Acute orbital haemorrhage is an ocular emergency requiring urgent treatment to prevent the usual previously reported outcome of permanent visual loss.
Energy dispersive X-ray analysis is recognized as a most useful technique in research. Its diagnostic applications are being rapidly developed. We describe a case of corneal, lenticular and retinal damage in an eye without a documented history of trauma. Scanning energy dispersive X-ray analysis of foreign material in the lens helped to elucidate the probable cause of the injury. The medico-legal implications of this case are briefly discussed.
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