1,721,061 research outputs found
Antibacterial activity of the female reproductive accessory gland secretion of Ceratitis capitata: purification and amino acid sequence of two peptides
No full textThe female accessory gland secretion from the medfly Ceratitis capitata was found to have a potent activity against several Gram-negative and -positive bacterial strains. The purification and the primary structure of two peptides responsible for such antibacterial activity has been reported
Il secreto delle ghiandole riproduttive accessorie maschili in due Insetti con diversa modalità di trasferimento degli spermatozoi
No full textL'apparato riproduttore femminile di Ceratitis capitata (Insecta, Diptera): aspetti ultrastrutturali e biochimici. Tesi di dottorato di ricerca in Biologia Animale, 3° ciclo, Università degli studi di Siena. Biblioteche Nazionali di Roma e Firenze. 263 pp.
No full textLa tesi comprende studi morfologici e biochimici sull'apparato riproduttore femminile di Ceratitis capitata, principalmente spermateche, ghiandole accessorie e ovidutto comune (compresa la camera di fecondazione, qui descritta per la prima volta). Una breve parte è dedicata alle ghiandole accessorie di un altro dittero tefritide, Bactrocera oleae
Organizzazione strutturale del sito di copula e trasferimento degli spermi in Ceratitis capitata (Diptera). Simposio IV Biologia riproduttiva degli invertebrati: aspetti strutturali e molecolari.
No full textCeratotoxins, antibacterial sex-specific peptides from the medfly Ceratitis capitata.
No full textCtxs are a family of α-helical, cationic, 3 kDa antibacterial peptides secreted by the female reproductive accessory glands of the Mediterranean fruit fly Ceratitis capitata. These peptides were found to display strong antibacterial activity and weak hemolytic activity. When reconstituted into planar lipid bilayers chemically synthesized Ctxs formed voltage-dependent ion channels according to the barrel-stave model. A synthetic truncated CtxA molecule resulted to permeabilize the outer and inner membranes of Escherichia coli cells
Abnormal centrosomes in cold-treated Drosophila embryos
No full textIn this study we examine the effect on the centrosomes of cold treatment of early Drosophila embryos. Prolonged cold treatment during the mitotic divisions which lead to the formation of the blastoderm causes arrest at metaphase of the nuclear divisions. When examined with immunofluorescence microscopy the mitotic spindles show marked pole splitting with the formation of supernumerary and irregularly sized centers, all able to nucleate microtubules. In embryos recovered for longer periods the additional organizing centers become ring-shaped and lose their nucleating properties. Cold treatment of embryos during the cellularization of the blastoderm results in marked fragmentation of the centrosomes, but nucleating capacity is preserved. Sometimes the centrioles come away from the pericentriolar material and their structure is seen to be modified
La struttura dei centrosomi nell'embrione di Drosophila melanogaster (anno di pubblicazione: 1988) Tipo pubblicazione: atto di convegno Convegno: 52° Congresso dell'Unione Zoologica Italiana Sede: Camerino (Italia) Dal: 12/9/1988 al: 16/9/1988Da pagina 26 a pagina 26
No full textColours: human Vision and surroundings
Full text linkWe propose interdisciplinary teaching-learning sequences focusing on colours. How do we perceive colours? How do animals perceive it? How do some animals make unusual coloured liveries? The proposal was initially tested with high school students in a summer school, then it was discussed in a summer school for science teachers in order to enhance the interdisciplinary aspects. Finally, it was proposed and discussed in a training event for in-service science teachers. Involvement and motivation in the learning process were the main reactions expected and the forecasts were fully achieved
Comparative fine structural analysis of the male reproductive accessory glands in Bactrocera oleae and Ceratitis capitata (Diptera, Tephritidae)
No full textThe morphology and ultrastructure of the male reproductive accessory glands from Bactrocera oleae and Ceratitis capitata were comparatively investigated. In both insects, there are two types of glands, mesoderm- and ectoderm-derived, which open in the ejaculatory duct. The mesoderm-derived glands are sac-like in B. oleae and very long tubules in C. capitata, whereas the ectodermic glands, generally branched finger-like structures, are longer in B. oleae than in C. capitata. Despite their different morphology, the ultrastructure of the two types of glands is quite similar in both Tephritids. The epithelium of the mesoderm-derived glands consists of binucleate and microvillate secretory cells. In C. capitata, but not in B. oleae, the secretory cells contain smooth endoplasmic reticulum and, in the sexually mature males, enlarged polymorphic mitochondria. The gland lumen is filled with a dense or sometimes granulated secretion. The ectoderm-derived glands undergo a cycle of maturation, by which their epithelial cells form a large subcuticular cavity filled with an electrontransparent secretion. Electrophoretic analysis of accessory gland secretion reveals in both species the presence of low molecular weight protein bands. A major band of about 29 kDa or 30 kDa in B. oleae and C. capitata, respectively, is
revealed
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