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A huge progress has been achieved in mammalian in vitro technique. Instead, of the many trials to develop marine invertebrate cell cultures, only a few have obtained them and only from few tissues. Since in vitro cell culture of invertebrates could be very useful for many aspects of basic and applied science, in this work we investigate and describe the development of a technique for the establishment of cell cultures from gill, mantle and gonadic tissue of the Manila clam (Ruditapes philippinarum). We maintained viable cultures for up to 25 days. Culture viability and proliferation were tested with 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) and with trypan blue, while an antibody against the ATP-dependent RNA helicase VASA, a protein expressed in the germline, and in multipotent stem cells of some animals, was used to verify the presence of these cell types. Following the described protocol: 1) explant resulted the better source to obtain cell cultures, when compared to enzymatic dissociation; 2) cultures of suspended cells were viable for longer period than adherent cells; 3) cell cultures obtained from tissues sampled in September-October performed better compared to other periods of the year, regarding maintenance and growth; 4) the tissue from which we obtained longer-lived cell cultures was gonadic tissue, especially form samples that show more undifferentiated germ cells and more VASA-stained cells. This study describes the challenges concerning the development of in vitro culture techniques for aquatic invertebrates. [ABSTRACT FROM AUTHOR]

The use of calcium-phosphate casein on hypomineralized molars (molar incisor hypomineralization, MIH) has been proposed but not clinically investigated. Qualitative and quantitative effects of supplementation with a calcium-phosphate casein product on MIH molars were monitored over a period of three years. Molar replicas, minimally invasive biopsies and their SEM microphotographs, plus ESEM/EDX semi-quantitative peaks of elements present in affected enamel were evaluated. Mineralization, morphology, and porosity appeared markedly improved, with calcium and phosphate levels reaching almost normal levels at three years’ follow-up. The hypothesis tested was rejected, since calcium-phosphate casein improved enamel morphology in vivo. [ABSTRACT FROM PUBLISHER]

Foschi F, Nucci C, Montebugnoli L, Marchionni S, Breschi L, Malagnino VA, Prati C.SEM evaluation of canal wall dentine following use of Mtwoand ProTaper NiTi rotary instruments.International Endodontic Journal,37, 832–839, 2004.To compare using scanning electron microscopy (SEM) root canal walls following instrumentationin vitrowith two different rotary NiTi instruments. The hypothesis was that no difference should be observable between the experimental groups in terms of debris on canal walls and surface morphology.Twenty-four single-rooted human teeth were selected. Two types of NiTi instruments were used, Mtwo(Sweden&Martina, Padova, Italy) and ProTaper (Dentsply Maillefer, Ballaigues, Switzerland). Irrigation for both groups was performed after each instrument change with 5% NaOCl, 3% H2O2 and 17% EDTA solutions. Three different areas (coronal, middle and apical thirds) of the root canal were evaluated using SEM. The canal wall of each sample was assessed and compared using a predefined scale of four parameters, namely, smear layer, pulpal debris, inorganic dentine debris, surface profile. Data were analysed statistically using the Kruskal–Wallis test (anova).A statistically significant difference (P <0.01) was found between the apical third and the middle and coronal thirds for both groups. No difference was observable between instrumentation groups. In the apical third canal walls were often contaminated by inorganic debris and by smear layer. In the apical third, the surface profile was affected by uninstrumented regions, comprising dentine depressions and grooves in which predentine was still visible.Both instruments produced a clean and debris-free dentine surfaces in the coronal and middle thirds, but were unable to produce a dentine surfaces free from smear layer and debris in the apical third. The presence of deep grooves and depression on dentine walls in the apical third may well explain the presence of less-instrumented areas. [ABSTRACT FROM AUTHOR]