Absorption of oral aminoglycosides following bone marrow transplantation

Four patients with severe gastrointestinal reactions receiving oral "nonabsorbable" antibiotics for gut sterilization following bone marrow transplantation absorbed clinically significant amounts of aminoglycoside (gentamicin and/or tobramycin). Serum concentrations of 2.2, 2.6, 5.8, and 12.0 micrograms/ml were measured. Two of these patients had acute graft versus host reactions and two had severe mucositis following cytoreduction with intensive chemotherapy and irradiation. Nephrotoxicity occurred in the latter patients. One patient was studied in detail. Her hospital course and investigative results are presented. Four additional patients with mild gastrointestinal reactions following cytoreduction did not absorb gentamicin when their toxicity was maximal. Serum aminoglycoside determinations are necessary in patients receiving oral aminoglycosides for gut sterilization following bone marrow transplantation if moderate to severe gastrointestinal reactions occur.     

Clonally restricted insulin autoantibodies in a cohort of 2200 healthy blood donors

Summary Serum samples of 2200 blood donors were screened for anti-insulin IgG by enzyme-linked immunosorbent assay. Specificity of detected antibodies was verified by competition with an excess of insulin and observation that saturated anti-insulin IgG were no longer measurable. The upper limit of measured signal in the population was defined as the mean plus three SD. In the direct assay, 32 sera were positive. Among these, 22 (1%) contained saturable insulin antibodies (true positive) and 10 were non-saturable and considered as non-insulin-specific. The positive blood donors were requested to answer a questionnaire and according to their answers, none had ever received insulin, was a first degree relative of a Type 1 (insulin-dependent) diabetic patient or had experienced a hypoglycaemic episode. None of the 22 true positive sera detected by enzyme-immunosorbent assay bound ¹²⁵-I-insulin to any significant extent. The nine sera yielding the highest signal were further characterized with regard to heavy and light chains as well as species specificity of ligand. Anti-insulin IgG from healthy blood donors contained only one heavy (1 2/9; 3 7/9) and one light ( 8/9; 1/9) chain. Three sera were human insulin specific; two were non-species-specific; the other four bound insulin in the order human = porcine > bovine. These results indicate that low affinity clonally restricted antibodies against insulin are present in unselected blood donors with a prevalence of 1%.     

Techniques and instruments for cataract surgery

New techniques for cataract surgery have evolved around access to the cataract, a renewed interest in nuclear expression extracapsular techniques, and a near-completion of the developmental cycle of phacoemulsification back to the original "divide and conquer" strategies. Options to improve access to the cataract include surgical pupil revision, self-retaining iris retractors, and surgical techniques for operating through a small pupil. Nucleus expression through a capsulorhexis is facilitated by global hydrodissection and hydrostatic tilting of the nucleus before removal. New phacoemulsification strategies revolve around the Phaco-Chop method that emphasizes nuclear rim fracturing.     

Motivating staff through teamwork: process review and data display

Outlines four interconnecting factors which are essential to motivating staff: an understanding of the "psychology of excellence in teams"; establishing cross-functional quality improvement teams; understanding and reviewing processes of care and service; and the use of data display.     

Systemic effects of different perfluorochemical agents

Purpose: An intravitreal injection of Fluosol-DA leads to a higher alteration of the macrophage system of the retina than perfluorooctane and perfluorodecalin administered by the same route. The difference may be due to different kinds of oxidative damage caused by the three chemicals. To test the validity of this assumption, the degree of cell alteration, expressed as reduction of cytoplasmic motility, caused by these three perfluorochemicals was examined. Methods: Using the hepatic macrophage system of the rat, cell alteration was examined by magnetometry after intravenous application of various perfluorochemicals [emulsified perfluorodecalin (C₁₀F₁₈), perfluorooctane (C₈F₁₇Br) and Fluosol-DA (corresponding to a 20% emulsion of 70% perfluorodecalin and 30% perfluorotripropylamine, C₉F₂₁N)]. Results: After administration of high doses, all perfluorochemicals led to cytoskeleton alteration. This alteration, expressed as retardation of the relaxation period of ferromagnetic iron oxide particles, was most pronounced after administration of Fluosol-DA. Conclusion: The compromising effect of perfluoro-chemicals is dose dependent and differs among the three compounds tested, with Fluosol-DA showing the greatest decrease in cytoplasmic motility.     

Local effects of different perfluorochemical agents

Purpose: To clarify whether the prolonged presence of perfluorochemicals (PFC) in the vitreous cavity causes oxidative tissue damage and inflammatory response of the retina and, if so, what the process is. Methods: After three different perfluorochemicals [perfluorodecalin (C₁₀F₁₈), perfluorooctane (C₈F₁₈) and Fluosol-DA (corresponding to a 20% emulsion of 70% PFD and 30% perfluorotripropylamine, C₉F₂₁N)] had been in the vitreous cavity of rabbits for 2 weeks, lipid peroxide concentration and myeloperoxidase activity in the retina were determined. Results: Whereas only Fluosol-DA showed significant oxidative damage, the inflammatory activity was significantly increased in all groups. Conclusion: The increased myeloperoxidase activity and the observed oxidative damage of the retina seem to be the effect of both perfluorochemical-loaded macrophages and inflammatory-induced lipid peroxidation.     

Oxidative reactions in the tear fluid of patients suffering from dry eyes

Purpose: To evaluate whether products of oxidative and inflammatory reactions are detectable in the tear fluid of patients suffering from dry eyes. Methods: The tear fluid of 217 patients (397 eyes) was sampled. Criteria for grouping of the patients were (1) basic secretion test (sicca l: BST = 0–5 mm, n = 78 eyes; sicca 2: BST = 6–10 mm, n = 109 eyes) and (2) subjective symptoms (normal BST, burning, foreign body sensations, tearing, dryness of the eyes: n = 78 eyes). One group of healthy patients (normal BST, n = 132 eyes) served as controls. Lipid peroxide levels and myeloperoxidase activity, as parameters for oxidative tissue damage and inflammatory activity, were determined in the tear fluid. Those patients whose consent could be obtained were subjected to the rose bengal test (sicca 1: 56 eyes; sicca 2: 97 eyes; subjective symptoms: 44 eyes; controls: 49 eyes). The correlation between BST and rose bengal test results was calculated. Results: Lipid peroxides were significantly (P < 0.05) higher in the groups sicca 1 and subjective symptoms than in healthy controls, as was the inflammatory activity in groups sicca 1, sicca 2 and subjective symptoms. Additionally, the inflammatory activity in the group sicca 1 was significantly (P < 0.05) higher than in the groups sicca 2 and subjective symptoms. No evidence of a significant correlation between BST and rose bengal test results was observed. Conclusions: Both oxidative tissue damage and polymorphonuclear leukocytes indicating an oxidative potential occur in the tear film of patients suffering from dry eyes. These reactions lead to severe damage of the involved tissue. Free radicals and inflammation may be involved in the pathogenesis or in the self-propagation of the disease.