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Background: Non-arteritic anterior ischemic optic neuropathy (NAION) is a multifactorial disease that is caused by an infarction of the vessels that supply the optic nerve head. This study aims at evaluating the role of traditional and emerging cardiovascular risk factors on the development of NAION., Methods: A total of 85 newly diagnosed NAION patients and 107 age- and gender-matched healthy controls were studied. All participants underwent blood testing for homocysteine and lipoprotein(a). Plasma levels of vitamin B6 and B12, and folic acid were also determined. Plasma values of all these parameters were evaluated as continuous variables, by a logarithmic transformation. In addition, traditional cardiovascular risk factors were considered., Results: With univariate analysis, higher values of homocysteine and Lp(a) (OR 4.24, 95% CI 2.01-8.94, p < 0.0001; OR 1.32, 95% CI 1.04-1.67, p = 0.03, respectively) and lower values of vitamin B6 (OR 0.44, 95% CI 0.25-0.76, p = 0.003) were significantly associated with NAION. At multivariate analysis, adjusted for age, gender, smoking habit, hypertension, dyslipidemia, diabetes, sleep apnea, and thrombophilic risk factors, the higher homocysteine and Lp(a) values (OR 5.74, 95% CI 2.41-13.67, p = 0.0001; OR 1.27, 95% CI 1.01-1.63, p = 0.04) and lower vitamin B6 values (OR 0.42, 95% CI 0.23-0.77, p = 0.005) maintained their significant relationship with NAION., Conclusions: This study demonstrated that elevated plasma homocysteine and lipoprotein(a) levels, as well as low vitamin B6 levels, may increase the risk of developing NAION. A screening for these thrombophilic markers could be useful in subjects experiencing NAION.

The susceptibility to various biocides was examined in planktonic cells and biofilms of the obligate aerobe, PCBs degrader, Pseudomonas pseudoalcaligenes KF707. The toxicity of two antibiotics, amikacin and rifampicin, three metalloid oxyanions (AsO2(-), SeO3(2-), TeO3(2-)) and three metal cations (Cd2+, Ni2+, Al3+) was tested at two stages of the biofilm-development (4 and 24 h) and compared to planktonic cells susceptibility. Mature biofilms formed in rich (LB, Luria-Bertani) medium were thicker (23 microm) than biofilms grown in minimal (SA saccarose-arginine) medium (13 microm). Early grown (4 h) SA-biofilms, which consisted of a few sparse/attached cells, were 50-100 times more resistant to antibiotics than planktonic cells. Conversely, minor changes in tolerance to metal(loid)s were seen in both SA- and LB-grown biofilms. In contrast to planktonic cells, no reduction of TeO3(2-) to elemental Te0 or SeO3(2-) to elemental Se0 was seen in KF707 biofilms. The data indicate that: (a) metal tolerance in KF707 biofilms, under the growth and exposure conditions described here, is different than antibiotic tolerance; (b) KF707 planktonic cells and biofilms, are almost equally susceptible to killing by metal cations and oxyanions, and (c) biofilm-tolerance to TeO3(2-) and SeO3(2-) is not linked to metalloid reduction; this means that KF707 planktonic cells and biofilms differ in their physiology and strategy to counteract metalloid toxicity.

Tellurite (TeO3(2-)) is the most toxic and soluble oxyanion among tellurium (Te) compounds. The effects of the metalloid anion on the oxidative stress response of the obligate aerobe Pseudomonas pseudoalcaligenes KF707 were investigated. Cells treated with sub-lethal concentrations of TeO3(2-) showed neither adaptation to it nor cross-protection against oxidants such as 1,1'-4,4'-bipyridinium dichloride (paraquat, PQ2+), diazenedicarboxylic acid bis-N,N-dimethylamide (diamide), tert-butyl hydroperoxide (tBH) and hydrogen peroxide (H2O2). Notably, TeO3(2-) exerted a synergic effect on the toxicity of these latter oxidants. Tellurite was shown to decrease the cellular content of reduced thiols (RSH) with a consequent increase in the production of reactive oxygen species (ROS) and stimulation of the superoxide dismutase (SOD) activity. However, since the time course of ROS production by TeO3(2) (t1/2 > 30 min) was much slower than that with PQ2+ and/or diamide (t1/2