Edith Gaton

Transluminal carbon dioxide-laser catheter angioplasty for dissolution of atherosclerotic plaques

Carbon dioxide laser energy was used for the dissolution of atheromatous plaques. Flexible, nontoxic infrared optical fibers were used for the transmission of the carbon dioxide laser beam intraarterially. Dissolution of plaques and recanalization of obstructed arteries were achieved both in vitro and in vivo with controllable damage to the vessel walls.

Toxic Effects of Systemic Retinoids on Meibomian Glands

Systemic use of retinoids is common in the treatment of various dermatological disorders. Blepharitis and conjunctivitis have been reported in 20-45% of the patients following systemic treatment with 13-cis-retinoic acid. Our purpose was to study the histopathological changes in the eyelids caused by long-term systemic treatment of female New Zealand rabbits with isotretinoin (2 mg/kg) and etretinate (2 mg/kg). The histopathological evaluation showed degenerative changes in the meibomian gland acini, leading to cell necrosis and a decrease in the basaloid cells lining the acini walls. No evidence of acute or chronic inflammatory reaction was noted.

Effects of chlorocyclizine on pulmonary lipid metabolism in rats

Pulmonary lipidosis was induced in rats by including 0.36 and 0.54% chlorocyclizine in their diet. Chemical analyses of the lung tissue revealed a very marked increase in phosphatidylcholine concentration. Phosphatidylglycerol and phosphatidylinositol concentrations were also markedly increased. An increase in the phosphatidylcholine content was also observed in lavage fluid and macrophages. Microscopic examination of the cell fraction showed that almost all the cells of the lavage fluid were macrophages and that histochemically demonstrable acid esterase activity was mostly inversely related to storage of lipids in the cells. Sonication of macrophages isolated from normal or chlorocyclizine-treated rats yielded a soluble acid phospholipase (pH optimum, 4.0) and a neutral (pH optimum, 8.2) membrane-bound, CaCl2-dependent enzyme. An inhibitory effect of chlorocyclizine in vitro on the activity of the soluble phospholipase was shown.

Histochemical study on the pathogenesis of chlorocyclizine-induced pulmonary lipidosis

SummaryMale rats were fed a diet containing chlorocyclizine in high concentrations for about 3 weeks. They lost weight and showed respiratory distress. The lungs contained clusters of foam cells in the alveoli. Acid esterase staining revealed reduction of activity in alveolar cells presumed to be granular pneumocytes and absence of activity in the foam cells. The lipid showed in the foam cells could not be stained with Sudan dyes, except at high temperature, and was not stained by phospholipid and cholesterol procedures. This indicated that the stored lipids are probably solid at room temperature, consisting of saturated triglycerides and/or phospholipids. It is suggested that the lipid originated in the granular pneumocytes. The drug might have deranged the esterase-phospholipase activity in these cells and in the macrophages.

A Case of Aspergillotic Meningo-Encephalitis in an Infant

Summary A case of meningo-encephalitis due to Aspergillus in a six months-old infant is reported. The morphological lesions were described in detail. Brain involvement by Aspergillus, especially at this age is rare and may not be suspected clinically.

Silver Halide Fibers For Surgical Applications Of CO 2 Laser

Carbon dioxide laser energy was used for the dissolution of atheromatous plaques. Delivery system was based on a AgCl:AgBr fiber which was inserted in a loose teflon tube. The system was used to vaporize human plaques in vitro as well as blocked human arteries which were transplanted in dogs. Preliminary results indicate that a system based on a CO2 laser and an infrared transmitting fiber may be useful in cardiology.

Macrophage Activation in the Prevention or Regression of Atherosclerosis

Studies of our group, first presented at a meeting of the Israel Atherosclerosis Society in 1973, indicated that atheromatosis might be the result of imbalance between the amounts of lipids absorbed in — or synthesized by the intima and the amounts removed or metabolized. According to this notion the fate of intimal smooth muscle cells, whether they will or will not be transformed into foam cells and eventually burst with formation of a poltaceous lipoproteic mass, depends on the relationship between the lipid input and output processes. Absorption of lipids from the medium and synthesis are included here under the heading “input”, while export of lipids from the tissues to the circulation as well as catabolism are included under “output”.

The role of nerve lysosomal enzymes in the pathogenesis of denervation atrophy

SummarySection of sciatic nerves of rats produced fibrillations within 3 days. Foci of hyalination leading to necrosis corresponded to segments of muscles containing end plates. The electrolyte content, mainly Ca, was increased, NADH2-TR activity was decreased and membrane ATP-ase was increased.The known increase in hydrolytic enzyme activities in denervated muscles was due to spilling of lysosomal enzymes from degenerating axons at the myoneural junction. This explains the discrepancy between morphological studies indicating paucity of lysosomes in normal muscles and the high hydrolytic enzyme activities in denervation. We propose that denervation changes are at least partly due to the effect of lysosomal spillage from degenerating axons.

THE PITUITARY-THYROID AXIS EFFECTS ON OCULAR AND ORBITAL TISSUES : A HISTOLOGICAL, HISTOCHEMICAL, AND MORPHOMETRIC STUDY

This work tests the notion that the effect of thyroid hormone on orbital and ocular tissues is mediated through its action on their lysosomal enzymes. Hyperthyroidism was produced in guinea pigs by thyroxin and TSH; hypothyroidism was induced by thiouracil. After treatment for 10 to 21 days, several ocular and orbital tissues were taken for histological, morphometrical, and histochemical examinations. High acid phosphatase activity was demonstrated in extraocular muscles, optic nerve and the retinal pigment epithelium of thyroxine- and TSH-treated animals. The findings fit the notion that the effects of thyroid hormones are mediated through lysosomes also in ocular and orbital tissues.