Enhanced ready biodegradability screening tests for the evaluation of potential PBT substances

In persistence assessment enhanced ready biodegradation tests (eRBT) are aimed to close the gap between screening tests and complex simulation tests. However, only few data from these tests are available and neither guidance on the design and interpretation of eRBTs, nor suitable validity criteria have been established so far. In a practical testing programme 5 compounds with controversial degradation data have been tested in 4 test series including prolongation to 60 days and use of different inocula (activated sludge, final effluent from a STP), flask sizes, and endpoints (CO₂, O₂, DOC). The drug ibuprofen and the intermediate 4-fluorophenol were biodegraded by >60% within 28 days within a 10-day-window and therefore are considered as readily biodegradable and in conclusion fulfilling the criteria for "not persistent". The mean mineralization of the pesticide synergist piperonylbutoxide and the antioxidant octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate achieved 20%-50% (="potentially P"). The mineralization of the cosmetic ingredient cis-13-docosenonamide (Erucamide) was between 36%-64% after 60 days with activated sludge and 21% with the effluent from the STP. Diethylene glycol reached the pass level of 60% mineralization within 28 days in all test series without always meeting the 10-day window, and thus proved to be a suitable reference substance for eRBTs. Based on the results of the study several recommendations for the test design, the evaluation and the interpretation of eRBTs are made. However, a broader data set is required and further enhancements such as the quality and amount of the inoculum should also be considered in future research.

Can a genetically-modified organism-containing diet influence embryo development? A preliminary study on pre-implantation mouse embryos

In eukaryotic cells, pre-mRNAs undergo several transformation steps to generate mature mRNAs. Recent studies have demonstrated that a diet containing a genetically modified (GM) soybean can induce modifications of nuclear constituents involved in RNA processing in some tissues of young, adult and old mice. On this basis, we have investigated the ultrastructural and immunocytochemical features of pre-implantation embryos from mice fed either GM or non- GM soybean in order to verify whether the parental diet can affect the morpho-functional development of the embryonic ribonucleoprotein structural constituents involved in pre-mRNA pathways. Morphological observations revealed that the general aspect of embryo nuclear components is similar in the two experimental groups. However, immunocytochemical and in situ hybridization results suggest a temporary decrease of pre-mRNA transcription and splicing in 2-cell embryos and a resumption in 4-8-cell embryos from mice fed GM soybean; moreover, pre-mRNA maturation seems to be less efficient in both 2-cell and 4-8-cell embryos from GM-fed mice than in controls. Although our results are still preliminary and limited to the pre-implantation phases, the results of this study encourage deepening on the effects of food components and/or contaminants on embryo development.

Visual perceptual dysfunction in patients with schizophrenic and affective disorders versus control subjects

Visual perception was evaluated with standard tests for 26 hospitalized patients with schizophrenia, 23 hospitalized patients with affective disorders, and 60 control subjects. Both patient groups differed significantly from the control group on low amplitude of accommodation, esophoria or exophoria, vergence duction suppression, and convergence and divergence recovery ductions. Only the affective group showed significantly reduced fusion at near distance, and only the schizophrenic group differed significantly from control subjects on disorganized left apex formation. These findings appear to confirm the presence of visual perceptual disorders that can cause disability in psychiatric patients, with important research and rehabilitation implications.

[The place of apatite in rheumatic diseases. Study of 25 cases by x-ray microanalysis and scanning electron microscopy]

The importance of "apatite deposition disease" among the arthropathies has been recognized for some years: it is well known that X-ray microanalysis (XRMA) is an efficient method of determining the elemental constitution of microcrystalline deposits obtained from synovial fluids or from tendon washing solutions during examination in scanning electron microscopy. In all 25 patients studied (11 intraarticular and 14 extraarticular samples), alizarine red S staining was positive and XRMA confirmed the diagnosis of apatite deposition by determination of the phosphorus/calcium (P/Ca) ratio in the deposits. In the 25 patients the mean values obtained for the P/Ca ratios were situated between 0.362 and 0.450, with a general mean value of 0.411, i.e. a ratio clearly lower than the P/Ca ratio of pure hydroxyapatite specimens (0.438) measured in identical conditions. This apparent discrepancy seems to be related to the probable presence of carbonated apatites. The study confirmed the presence of apatite microcrystals in intra- and extraarticular location; in the first condition, these were generally found in patients with severe destructive arthrosis, whereas in the second condition the calcifications derived from supraspinatus tendons.