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This paper reports information about the presence of three allochthonous reptiles species in Calabria: Testudo marginata, Trachemys scripta elegans and Chamaeleo chamaeleon. The first one was found in three sites located in the Catena Costiera Massif and in the Crati Valley (Northern Calabria). The slider turtle was found in seven different sites throughout all the region. It massively colonised the Angitola artificial lake: here, this turtle lives in natural conditions and its reproduction was confirmed by the presence of nests, eggs and hatchlings. C. chamaeleon is present in sandy coastal habitats near Palmi and Gioia Tauro (Southern Calabria). From a conservationistic point of view, serious damages to autochtonous species could be caused by the spreading of T. scripta elegans: this species has already determined the local extinction of Angitola's Emys orbicularis populations. [ABSTRACT FROM AUTHOR]

Previous studies have suggested that 1α,25-dihydroxyvitamin D3[1,25(OH)2D3] has a role in reproductive function. Gonadal insufficiencies were observed as a result of 1,25(OH)2D3 deficiency and in 1,25(OH)2D3 receptor (VDR) null mutant mice. To study human sperm anatomy at the molecular level, we first evaluated the ultrastructural localization of VDR by immunogold electron microscopy using a monoclonal antibody against amino acids 344–424 of human VDR, in normozoospermic samples. Intriguingly, VDR was associated predominantly with the cell nucleus. In fact, it is known that VDR is a transcription factor, and that in vitamin-D-depleted animals, VDR is largely localized in the cell nucleus. To assess the significance of VDR in the male gamete, we investigated the role of 1,25(OH)2D3/VDR in sperm survival and capacitation. Our results revealed that the action of 1,25(OH)2D3 depended on its concentration because although lower doses induced cholesterol efflux, protein phosphorylation and sperm survival, a higher concentration seemed to be ineffective or did not show an increased effect. These results increase our knowledge of human sperm anatomy at the molecular level and suggest that 1,25(OH)2D3/VDR may have an important role in sperm survival and the acquisition of fertilizing ability. [ABSTRACT FROM AUTHOR]

Abstract: We analysed the morphology and ultrastructure of the gill apparatus of the ornate wrasse, Thalassoma pavo, under normal conditions and after exposure to a sublethal concentration of sodium lauryl sulphate (3.5mg/l, which is one-third of the 96LC99 value). To identify the biochemical mechanisms affected by this pollutant, we evaluated and compared the localisation of Na+/K+ ATPase in normal and experimental conditions. Immunocytochemical analysis revealed that this enzyme was active in the chloride cells (CCs), which were distributed in clusters in the interlamellar region of the filament. Ultrastructural analysis revealed conspicuous alterations on the epithelium after 96 and 192h of exposure to sodium lauryl sulphate: structural features of the surface cells were lost, the appearance of intercellular lacunae changed, and cellular degeneration occurred. Statistical analysis comparing the number and dimensions of CCs in normal conditions and after 96h of exposure showed that the CC area decreased after exposure to the detergent. [Copyright &y& Elsevier]

During the 2000-2009, a survey study on the spatiotemporal patterns of distribution of large predatory sharks was carried out in the Calabria region. A total of 12 species were recorded and among them the blue shark Prionace glauca and the bluntnose sixgill shark Hexanchus griseus were the most common ones. Also of interest was the frequency of species such as Carcharodon carcharías, Sphyrna zygaena and Cetorhinus maximus. 57% of all reported records derived from the Tyrrhenian side of the region and 43% on the Ionian side. A significant relationship between season of the year versus number of records was found, but this could be related to the small number of observers that were active during the winter months. The presence of Sphyrna lewini ¿s reported for the study area; this species was previously recorded only in the western part of the Mediterranean Sea. This paper also provides evidence of the second and first documented accounts of white shark prédation upon Tursiops truncatus and Stenella coeruleoalba, respectively, in the Mediterranean Sea. The recovering of Ionian Sphyrna zygaena populations and the declining q/Uamna nasus populations were also noted. [ABSTRACT FROM AUTHOR]

Endosulfan sprayed on agricultural fields accumulates in temporary pools due to surface runoff or sediment transport and may result in high water concentrations in spring and summer, coinciding with breeding and crucial stages of amphibian larval development. In the present study, Bufo bufo tadpoles were exposed to three different concentrations of endosulfan (0.01, 0.05 and 0.1 mg/L) until they reached complete metamorphosis. The aim of the study was to investigate the effects of endosulfan, at environmentally relevant concentrations on gill morphology and ultrastructure. Modifications in ultrastructure and cell composition were observed at all concentrations after 96 h. The main gill effects recorded in treated animals were: mucous secretion, the appearance of tubular vesicles cells (TVC) and a degeneration phenomenon. Comparing these results with our previous findings in which we used growth, developmental rate and behaviour as endpoints, we also demonstrated that the first effect of endosulfan on Bufo bufo was gill alteration, thus supporting the role of a morphological approach in toxicological studies. This study provides additional information on the role of morphological studies in demonstrating the effects of exposure to environmental pollutants. In this context, the use of amphibian gills, as effective biomarkers, is a valuable approach in evaluating exposure to agrochemicals.

The sperm of Caprimulgus europaeus is typical of other nonpasserines in many respects. Features shared with Paleognathae and Galloanserae are the conical acrosome, shorter than the nucleus; the presence of a perforatorium and endonuclear canal; the presence of a proximal as well as distal centriole; the elongate midpiece with mitochondria grouped around a central axis (here maximally six mitochondria in approximately 10 tiers); and the presence of a fibrous or amorphous sheath around the principal piece of the axoneme. A major (apomorphic) difference from paleognaths and galloanserans is the short distal centriole, the midpiece being penetrated for most of its length by the axoneme and for only a very short proximal portion by the centriole. Nonpasserines differ from paleognaths in that the latter have a transversely ribbed fibrous sheath, whereas in nonpasserines it is amorphous, as in Caprimulgus, or absent. The absence of an annulus is an apomorphic feature of Caprimulgus, apodiform, psittaciform, gruiform, and passerine sperm, homoplastic in at least some of these. In contrast to passerines, in Caprimulgus the cytoplasmic microtubules in the spermatid are restricted to a transient longitudinal manchette. The structure of the spermatid and spermatozoon is consistent with placement of the Caprimulgidae near the Psittacidae, but is less supportive of close proximity to the Apodidae, from DNA-DNA hybridization and some other analyses., (Copyright (c) 2006 Wiley-Liss, Inc.)

Our previous work showed that low-power wide-band millimeter waves (MMW) inhibit the growth of the MCF-7 human breast carcinoma cell line, also causing a marked reduction of the density of microvilli at the apical membrane of the MCF-7 cells, as revealed by scanning electron microscopy. The aim of the present work was to investigate the ultrastructural changes induced by such electromagnetic radiations on this cell line. A transmission electron microscopy study was performed on MCF-7 cells irradiated under the same experimental conditions previously adopted. Transmission electron microscopy analysis revealed several ultrastructural features of the MMW-irradiated cells pertinent to cells subjected to sublethal injury. The antiproliferative effect of the millimeter radiation was confirmed. MMW, in the 52-78 GHz frequency range, act as stress factor on the cells that survive in a non-steady low-mitogenetic metabolic state.

The effects of low power millimetric wave (MMW) radiation on the growth of tumor and healthy cells were studied. A wide-band frequency range between 53.57-78.33 GHz with a radiation density power of 27 x 10(-17) watt/Hz were used. The radiating energy was low enough not to increase the temperature of the cellular samples (cold irradiation). One hour of radiation treatment given every other day to three tumoral human stable cell lines, produced a noticeable inhibition of the cellular growth. The analogous treatment given to two healthy cell lines gave a weak growth stimulation. A scanning electron microscopy study of MCF-7-and K562-irradiated cells revealed that MMW irradiation induced profound morphological changes of the membrane. Finally, we also provided a mechanistic indication, based on millimeter wave spectroscopy of the cells: water is the primary absorber of these electromagnetic waves. Our work provides interesting evidence that wide band low power MMW irradiation, in the appropriate frequency range, could be used in the future as a cold means to cause selective inhibition of tumor cell growth.

The mature spermatozoon of Admetus pomilio is a spherical cell containing nucleus and tightly coiled flagellum. In early spermatids the Golgi apparatus forms the acrosomal vesicle and at the opposite side the distal centriole gives rise to the axonemal complex of the sperm tail. As the nucleus elongates, chromatin forms twisted filaments and the spermatid nucleus takes on a helical form. Microtubules are juxtaposed with the nucleus envelope, which is separated from a central chromatin mass by an electron lucid region. A long perforatorium, located on the border of the chromatin mass, runs helically in the nucleus from the centriolar region to subacrosomal space. During tail elongation, the anterior part of the axoneme is surrounded by a long, spiral mitochondrial sheath. In the late spermatid, chromatin filaments appear twisted and become aggregated. The nucleus and flagellum undergo further contortions in which the nucleus coils and the flagellum winds up into the body of the cell and coils in a regular fashion. The mitochondrial sheath surrounds about 2/3 of the 9 + 3 axoneme. These features of spermatid ultrastructure resemble those in the primitive Liphistiomorpha., (Copyright © 1985 Wiley-Liss, Inc.)