Relationship between Antioxidant Activity and Ligand Basicity in the Dipicolinate Series of Oxovanadium(IV) and Dioxovanadium(V) Complexes.

Oxidative stress plays an important role in the pathogenesis of many serious diseases, including cancer, atherosclerosis, coronary artery disease, Parkinson's disease, Alzheimer's disease, stroke and myocardial infarction. In the body's natural biochemical processes, harmful free radicals are formed, which can be removed with the help of appropriate enzymes, a balanced diet or the supply of synthetic antioxidant substances such as flavonoids, vitamins or anthocyanins to the body. Due to the growing demand for antioxidant substances, new complex compounds of transition metal ions with potential antioxidant activity are constantly being sought. In this study, four oxovanadium(IV) and dioxovanadium(V) dipicolinate (dipic) complexes with 1,10-phenanthroline (phen), 2,2'-bipyridyl (bipy) and the protonated form of 2-phenylpyridine (2-phephyH): (1) [VO(dipic)(H2O)2]·2 H2O, (2) [VO(dipic)(phen)]·3 H2O, (3) [VO(dipic)(bipy)]·H2O and (4) [VOO(dipic)](2-phepyH)·H2O were synthesized including one new complex, so far unknown and not described in the literature, i.e., [VOO(dipic)](2-phepyH)·H2O. The oxovanadium(IV) dipicolinate complexes with 1,10-phenanthroline and 2,2'-bipyridyl have been characterized by several physicochemical methods: NMR, MALDI-TOF-MS, IR, but new complex [VOO(dipic)](2-phepyH)·H2O has been examined by XRD to confirm its structure. The antioxidant activities of four complexes have been examined by the nitrotetrazolium blue (NBT) method towards superoxide anion. All complexes exhibit high reactivity with superoxide anion and [VOO(dipic)](2-phepyH)·H2O has higher antioxidant activity than L-ascorbic acid. Our studies confirmed that high basicity of the auxiliary ligand increases the reactivity of the complex with the superoxide radical.

Ranibizumab after laser photocoagulation failure in retinopathy of prematurity (ROP) treatment.

The purpose of this study was to investigate the anatomical and functional outcomes of the two-stage treatment of severe retinopathy of prematurity (ROP) using laser photocoagulation and intravitreal ranibizumab injection. The medical records of 53 eyes of 28 infants treated by conventional laser photocoagulation with deferred intravitreal 0.25 mg/0.025 mL ranibizumab injection were analysed. All patients had at least 11 months of follow-up. In the analysed group, the mean gestational age at birth was 25 weeks and mean birthweight was 790 g. The mean time of laser photocoagulation was 34 weeks of postmenstrual age (PMA). Ranibizumab injection was performed on average at 37 weeks of PMA. The mean time between interventions was 19 days. Retinal detachment occurred in 12 eyes (22.6%), in three children bilaterally. Visual responses were obtained in 23 of 28 treated children. Our results indicate that ranibizumab injection can be taken into consideration in the selected cases of laser photocoagulation failure. The unsatisfactory results of this study elicited a change in the ROP treatment protocol in our medical centre. The study gives an insight into anatomical and functional outcomes of ROP treatment in the Central and Eastern European population.

Morphologic, Electrophysiologic, and Visual Function Parameters in Children with Non-Glaucomatous Cupping of Prematurity.

The aim of this study was to compare morphologic, electrophysiologic, and visual function parameters in non-glaucomatous cupping of prematurity to those of controls. Twenty children (7 to 18 years) with non-glaucomatous cupping of prematurity were prospectively recruited, along with 20 controls. Visual function parameters, retinal nerve fiber layer (RNFL) thickness, and visual evoked potentials (VEP) parameters were measured. RNFL thickness was reduced in children with non-glaucomatous cupping of prematurity compared with controls. VEP P100 amplitude was significantly lower in children with non-glaucomatous cupping of prematurity than in the control group. Kinetic perimetry visual fields were normal in all but one patient. Static perimetry revealed increased overall pattern defect in children with non-glaucomatous cupping of prematurity compared with controls. Despite these morphological, electrophysiological, and subtle visual field defects, many other visual function parameters, such as visual acuity, color vision, and contrast sensitivity, appear similar to normal controls.