Validation of the SkinEthic HCE Time-to-Toxicity test method for eye hazard classification of chemicals according to UN GHS.

This study describes the within- and between-laboratory reproducibility (WLR and BLR) of a Time-to-Toxicity (TTT) approach for chemicals based on the SkinEthic™ HCE tissue construct, capable to distinguish chemicals that do not require classification for serious eye damage/eye irritation (No Cat.) from chemicals that require classification for eye irritation (Cat. 2), and serious eye damage (Cat. 1). The WLR and BLR was assessed with three participating laboratories. Each laboratory tested 40 coded chemicals in three independent runs. The predictive capacity of the method was assessed on a larger set of 150 chemicals (70 liquids and 80 solids) by combining the results of this study with the results of the test method developer. The WLR for the 20 liquids ranged from 85% to 95% with a BLR of 90%. For the 20 solids, a WLR and BLR of 100% was obtained. The test method developer obtained a WLR of 80% and 95%, based on 50 liquids and 48 solids tested in three independent runs, respectively. Regarding the predictive capacity, the SkinEthic™ HCE TTT test method identified 80.8% Cat. 1, 69.2% Cat. 2, and 74.9% No Cat. correctly. An independent peer review panel concluded that based on all available data, the relevance and reliability of the SkinEthic™ HCE TTT has been demonstrated for discriminating the three UN GHS eye hazard categories.

Amino acid and hyaluronic acid mixtures differentially regulate extra cellular matrix genes in cultured human fibroblasts.

The aim of this screening study was to evaluate the efficacy of different proprietary mixtures of amino acid and hyaluronic acid (HA) in stimulating the production of extracellular matrix (ECM) components, particularly the neo-synthesis of elastin, and in promoting a more efficient deposition of elastic fibres (elastogenesis), while at the same time maintaining the stimulation of collagen. The study has allowed identification of the optimal ratios between the amino acids (AA) for the production of collagen and elastin. Human primary dermal fibroblasts from a 44-year-old female donor were used as a test system in an experimental design based on the evaluation of the expression of relevant ECM genes using a transcriptomic dynamic approach. The expression of ECM genes was evaluated by RTqPCR from 24 to 120 hours in the presence of the test items. Moreover, the production of ECM proteins was verified by Western blot analysis after a 120 h treatment period. In addition to elastin, collagen IV, a fundamental structural component of the basal lamina responsible for epithelial and connective tissue anchoring, was analysed as potential target for the modulation of ECM protein production by human fibroblast. The first phase of the study demonstrated that alanine and valine are essential to promote production of elastin, of which they are important constituents. The second phase of the study, which was conducted to clarify the interactions between the different clusters of AA, demonstrated that it is necessary to choose a mixture that contains specific amounts of amino acids of both proteins, collagen and elastin, to give a significant response and a significant production of both. This also proves the existence of a ratio between the 2 clusters (AA elastin/AA collagen) that guarantees an adequate and balanced response to gene expression and production by fibroblasts, collagen and elastin. The study has allowed identification of the optimal ratios between the AA for the production of collagen and elastin.

Decrease of TGF-beta1 plasma levels and increase of nitric oxide synthase activity in leukocytes as potential biomarkers of Alzheimer's disease.

A variety of inflammatory proteins have been identified in brains of Alzheimer's disease (AD) patients, including inflammatory cytokines, acute phase proteins and complement components. In the present paper we have investigated the levels of circulating inflammatory mediators as potential biomarkers of this disease, concentrating mostly on transforming growth factor beta (TGF-beta1) in plasma and on nitric oxide synthase (NOS) activity in leukocytes. Plasma and leukocytes were isolated from 48 sporadic AD and 23 healthy control subjects of same age and sex. Since alpha2-Macroglobulin (alpha2M), an acute phase protein possibly involved in AD, is an important modulator of TGF-beta1 activity, binding and targeting this cytokine to its appropriate site of action, we have investigated the possible complex between TGF-beta1 and alpha2M in plasma of the same subjects. The results demonstrate a significant reduction of TGF-beta1 levels in plasma of AD patients. A complex between alpha2M and TGF-beta1 occurred in AD as well as healthy elderly control subjects, however, with no significant differences. Moreover, alpha2M appeared to bind only the inactive form of this cytokine. In contrast, NOS activity increased significantly in leukocytes of AD patients. Therefore, we suggest the combined determination of TGF-beta1 in the plasma and of NOS activity in the leukocytes as biomarkers of AD.

[Application of PCR in the diagnosis of B-type non-Hodgkin's lymphomas in cytological specimens from fine-needle aspiration]. / Applicazione della PCR nella diagnosi di linfomi non Hodgkin di tipo B su campioni citologici da agoaspirazione.

UNLABELLED: The application of PCR to detect monoclonality at the immunoglobulin heavy chain gene locus in FNA cytologic specimens was evaluated. MATERIALS AND METHODS: Immunoglobulin heavy chain gene rearrangement analysis was performed by a nested PCR for the VDJ region on 27 lymph nodes FNA paraffin embedded by cell blocking technique specimens (1 suspicious of NOS lymphoma, 1 Hodgkin's disease, 6 B cell non Hodgkin's lymphomas, 10 reactive hyperplasias). RESULTS: A monoclonal band was seen in 13 of 17 suspicious or positive malignant cases. The other 4 specimens gave a policlonal pattern. Specimens from reactive lymph nodes produced policlonal bands in 8 cases, no product in 1 case and 1 specimen gave a monoclonal band. When needed, the results of PCR examinations were compared with the subsequent histologic evaluation of the same lymph-node. CONCLUSIONS: From our experience we can see that clonal analysis by PCR based IgH gene rearrangement analysis can be applied to FNA material and can be useful in diagnosis.