Unitus DSpace

Fine structure of the eggshell of Ommatissus binotatus Fieber (Homoptera, Auchenorrhyncha, Tropiduchidae)

2011-05-25T15:17:51Z

Title: Fine structure of the eggshell of Ommatissus binotatus Fieber (Homoptera, Auchenorrhyncha, Tropiduchidae) Authors: Guglielmino, Adalgisa; Taddei, Anna Rita; Carcupino, Marcella Abstract: The external morphology and fine structure of the eggshell of Ommatissus binotatus Fieber (Homoptera: Tropiduchidae) was investigated by light, scanning, and transmission electron microscopy. The egg surface has 2 main regions: a specialized area and an unspecialized egg capsule. The specialized area is characterized by a large respiratory plate containing the operculum and a short respiratory horn. The latter consists of an external hollow tube and an internal cone-shaped projection hosting a micropylar canal. The eggshell has 4 layers: the vitelline envelope, a wax layer, the chorion and an outer mucous layer. The chorion has inner, intermediate, and outer parts. The functions of the different parts of the eggshell are discussed. Characters useful to define the eggs and the oviposition habit in the family Tropiduchidae were provided. The size and morphology of the egg, plate, respiratory horn, and operculum are suggested as useful characters for ootaxonomic analysis.

The parthenocarpic fruit (pat) mutant of tomato (Lycopersicon esculentum Mill.) sets seedless fruits and has aberrant anther and ovule development

2011-06-30T14:40:17Z

Title: The parthenocarpic fruit (pat) mutant of tomato (Lycopersicon esculentum Mill.) sets seedless fruits and has aberrant anther and ovule development Authors: Mazzucato, Andrea; Taddei, Anna Rita; Soressi, Gian Piero Abstract: Among the different sources of genetic parthenocarpy described in tomato, the mutation referred to as parthenocarpic fruit (pat) is of particular interest because of its strong expressivity and because it confers better earliness, higher fruit set and enhanced fruit quality. As a pleiotropic effect, pat flowers have aberrantly developing androecia and reduced male and female fertility. In this work we extend the early description of the pat phenotype by investigating the expression of parthenocarpy in three different environments and by using light and scanning electron microscopy to analyse the development of male and female floral organs. The degree of parthenocarpy was high in the three experimental environments and was characterised by an initiation of ovary growth anticipated to pre-anthesis floral stages. Aberrations in anther development were evident at flower bud stages and resulted in shorter, irregular and teratoid organs. Ectopic production of carpel-like structures bearing external ovules was evident in the most severely altered androecia. Analysis of ovule development revealed that a fraction of pat ovules becomes aberrant from very early stages, having defective integument growth. Meiosis was irregular in aberrant ovules and megaspores or gametes production was severely hampered. The described pat syndrome suggests that parthenocarpy in this mutant could be a secondary effect of a gene controlling, at early stages, organ identity and development. Description: L'articolo é disponibile sul sito dell'editore: http://dev.biologists.org/

Sperm quality and reproductive traits in male offspring of female rabbits exposed to Lindane (γ-HCH) during pregnancy and lactation

2011-04-05T00:30:29Z

Title: Sperm quality and reproductive traits in male offspring of female rabbits exposed to Lindane (γ-HCH) during pregnancy and lactation Authors: Fausto, Anna Maria; Morera, Patrizia; Margarit, Rita; Taddei, Anna Rita Abstract: Fifteen Grimaud female hybrid rabbits, 135 days old and weighting an average of kg each, were administered an oral dose of 1 mgkg-1 body weight of Lindane during gestation and lactation period. Fertility rate, libido, volume of ejaculate, concentration and morphology of spermatozoa were investigated to test the effects of the treatment on reproductive traits of first generation male rabbits. Ultrastructure of abnormal spermatozoa was described by Transmission Electron Microscopy and the different abnormalities were quantified. The results obtained indicate that low dose exposure of Lindane has effects on spermatozoa ultrastructure that proved to be susceptible to the treatment with the pesticide (cytoplasmic droplets: 5.3% in control group and 10.3% in Lindane group, ; coiled tails: 1.3% in control group and 4.3% in Lindane group, ) and could be utilised as a good marker of toxicity

Early treatment with Lactobacillus delbrueckii strain induces rise in intestinal T cells and granulocytes and modulates immune related genes of larval Dicentrarchus labrax (L.)

2011-06-28T09:12:14Z

Title: Early treatment with Lactobacillus delbrueckii strain induces rise in intestinal T cells and granulocytes and modulates immune related genes of larval Dicentrarchus labrax (L.) Authors: Picchietti, Simona; Fausto, Anna Maria; Randelli, Elisa; Carnevali, Oliana; Taddei, Anna Rita; Buonocore, Francesco; Scapigliati, Giuseppe; Abelli, Luigi Abstract: Lactobacillus delbrueckii ssp. delbrueckii (AS13B), isolated from the gut of adult Dicentrarchus labrax, was administered live to developing sea bass using rotifers and Artemia as live carriers. Immune-related gene transcripts were quantified in post-larvae at day 70 post-hatch (ph) and histology, electron microscopy and immunocytochemistry of the intestinal tissue were performed at day 74 ph. Since the probiotic was orally administered the studies were focused on intestinal immunity. In treated fish gut integrity was unaffected, while the density of T-cells and acidophilic granulocytes in the intestinal mucosa was significantly higher than in controls. Probiotic-induced increases in intestinal T-cells and total body TcR-beta transcripts are first reported in fish. Significantly lower IL-1beta transcripts and a trend towards lower IL-10, Cox-2 and TGF-beta transcription were found in the treated group. Evidence is provided that early feeding with probiotic-supplemented diet stimulated the larval gut immune system and lowered transcription of key pro-inflammatory genes. Description: L'articolo è disponibile sul sito dell'editore http://www.sciencedirect.com/

Effects of administration of probiotic strains on GALT of larval gilthead seabream: immunohistochemical and ultrastructural studies

2011-07-04T19:17:53Z

Title: Effects of administration of probiotic strains on GALT of larval gilthead seabream: immunohistochemical and ultrastructural studies Authors: Picchietti, Simona; Mazzini, Massimo; Taddei, Anna Rita; Renna, Raffaella; Fausto, Anna Maria; Mulero, Victoriano; Carnevali, Oliana; Cresci, Alberto; Abelli, Luigi Abstract: Two bacterial strains Lactobacillus fructivorans (AS17B), isolated from adult seabream (Sparus aurata L.) gut, and Lactobacillus plantarum (906), isolated from human faeces, were administered contemporaneously during seabream development using Brachionus plicatilis and/or Artemia salina and dry feed as vectors. Experimental group A received the probiotic strains already via rotifers from day 5 post-hatch (ph), whereas treatment of group B began with Artemia feeding from day 27 ph. Fish were sampled at day 28 ph (group A and control) and day 99 ph (groups A, B and control) for electron microscopy, histology and immunohistochemistry with the polyclonal antiserum ORa against homologous serum Ig and the mAb G7 specific for seabream acidophilic granulocytes. In all groups, timing and pattern of differentiation of the digestive tract did not differ. Furthermore, neither tissue damage nor manifest inflammation was provoked by probiotic administration. At day 28 ph, the developing GALTalready housed mucosal leucocytes, including Igþ cells but no acidophilic granulocytes. No differences were seen between experimental groups. At day 99 ph, the density of Igþ cells (þ51%) and acidophilic granulocytes (þ284%) was significantly higher (p < 0.05) in group A than in controls. Also group B had a higher density of Igþ cells (þ17%) and acidophilic granulocytes (þ130%) compared with controls, although less pronounced. Light and electron microscopy observations detailed the occurrence of heterogeneous populations of lymphocytes and granulocytes in the developing intestinal mucosa, and highlighted the net expansion of G7þ acidophilic granulocytes (A þ536%, B þ292% vs. control) due to probiotic administration. Description: L'articolo è disponibile sul sito dell'editore http://www.sciencedirect.com/

The thyroid disruptor 1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane (DDT) prevents internalization of the TSH receptor

2011-07-04T19:02:17Z

Title: The thyroid disruptor 1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane (DDT) prevents internalization of the TSH receptor Authors: Picchietti, Simona; Belardinelli, Maria Cristina; Taddei, Anna Rita; Fausto, Anna Maria; Pellegrino, M.; Rossi, M.; Maggio, Roberto; Giorgi, Franco Abstract: The thyroid-stimulating hormone (TSH) receptor (TSHr) was made specifically fluorescent by insertion of a tetracysteine motif (TSHr-FlAsH) into the C-terminal end and transiently transfected into COS-7 and HeLa cells. The observation that TSH administration caused the intracellular level of cAMP to increase in both TSHr-FlAsH-transfected cell types indicated that the FlAsH binding motif did not alter normal TSHr functioning. When transfected into HeLa cells and stimulated with TSH, the TSHr-FlAsH receptor exhibited a pronounced perinuclear labelling pattern, whereas labelling remained on the cell surface following pre-incubation with 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane (DDT). Chinese hamster ovary (CHO)-TSHr cells probed with anti-TSHr antibodies were fluorescent mainly in the proximity of the plasma membrane, with fluorescence being primarily restricted to a juxta-nuclear position when exposed to 10 mU/ml TSH for 1 or 5 min. However, in the presence of DDT, the anti-TSHr fluorescence maintained a peripheral location along the cell plasma membrane, even if CHO-TSHr cells were stimulated with TSH for 1 and 5 min. To verify that DDT acted specifically on the TSHr, CHO cells transfected with the A2a receptor were used as controls. Following a 1-min stimulation with 5’-(N-ethyl-carboxamido)-adenosine, A2a receptors were gradually internalized regardless of the presence of DDT in the culture medium. Finally, immunoelectron microscopy of CHO-TSHr cells showed that a 1-min exposure to TSH sufficed to displace anti-TSHr antibodies tagged with 10- nm gold particles into coated pits and vesicles but that their superficial location was retained along the plasma membrane in the presence of DDT. Description: L'articolo è disponibile sul sito dell'editore http://www.springerlink.com/

Dispositivi medici di collagene utilizzati come agenti emostatici e cicatrizzanti

2011-06-28T15:05:47Z

Title: Dispositivi medici di collagene utilizzati come agenti emostatici e cicatrizzanti Authors: Taddei, Anna Rita; Picchietti, Simona; Gambellini, Gabriella; Fausto, Anna Maria; Giorgi, F.; Cervadoro, E.; Ricciuti, F. Abstract: Quattro dispositivi medici di collagene sono stati esaminati al microscopio elettronico per determinare le migliori condizioni strutturali che ne giustificano il ruolo come agenti emostatici e cicatrizzanti. I parametri che sono stati considerati più efficaci per il processo di guarigione sono la struttura interstiziale e lo spessore dei fasci di collagene che la delimitano. Spazi interstiziali troppo grandi o troppo piccoli non sono in grado di sostenere la migrazione cellulare, mentre fasce di collagene troppo fini o troppo spessi possono influenzare il tempo di persistenza del dispositivo sulla ferita. Sulla base di questi criteri, è stato trovato che i campioni di Condress realizzano il miglior compromesso tra l'estensione della struttura interstiziale e lo spessore dei fasci di collagene.; Four collagen samples were examined at the electron microscope to find out the best structural conditions satisfying their haemostatic and cicatrizing roles. Parameters considered most effective during healing process are the mesh substructure and the thickness of the collagen strands. Meshes too large or too small may not be suitable for sustaining cell migration, while collagen strands too thin or too thick may affect the actual persistence of the medical device on the wounded area. Based on this criteria, Condress samples are thought to provide the best structural compromise between extension of the mesh areas and thickness of the collagen strands. Description: L'articolo è disponibile sul sito dell'editore http://www.seuroma.com/