1,102 research outputs found
Modificazioni stagionali della membrana basale dell’epitelio seminifero della lucertola Podarcis sicula Raf
No full textLa membrana basale regola l'attività dell'epitelio seminifero nei vertebrati a riproduzione stagionale.
In questo lavoro vengono illustrati i risultati di indagini istochimiche, immunoistochimiche ed
ultrastrutturali sulla membrana basale del testicolo di Podarcis sicula, in condizioni normali e
sperimentali. Gonadi di maschi adulti di Podarcis s. catturati nel periodo riproduttivo (maggio) e di
crisi estiva (luglio), alcuni trattati con estradiolo, sono stati: 1) fissati in liquido di Stieve, inclusi in
paraffina e le sezioni colorate con ematossilina-eosina, PAS e immunocolorate per la ricerca della
laminina e del collagene IV; 2) fissati in GTA 3%, post-fìssati in OsO4 1%, inclusi in Araldite e le
sezioni ultrafini osservate al TEM. La PAS reazione ha mostrato debole affinità per la membrana
basale in tutti gli esemplari che solo in luglio hanno evidenziato una netta colorazione della laminina,
mentre il collagene IV è stato ben marcato nei testicoli degli esemplari di maggio trattati con estradiolo
e, soprattutto, di luglio (trattati e non). Nel periodo riproduttivo la membrana basale (spessa 200 nm)
ha mostrato aspetto lineare mentre nel periodo di stasi estiva è apparsa notevolmente introflessa e
spessa 300 nm per incremento di ampiezza della lamina tìbroreticolare. Negli esemplari estrogenizzati
di luglio un materiale reti co lo granulare di origine ematica è stato imbrigliato e trattenuto dalla lamina
fibroreticolare. In conclusione, la membrana basale dei tubuli seminiferi di lucertola subisce
modificazioni strutturali e molecolari correlate con l'attività testicolare stagionale e svolge anche un
ruolo di barriera molecolare con compiti di protezione dell'epitelio seminifero
Modificazioni stagionali dell'ultra struttura della ghiandola androgenica del gambero Aristaeomorpha foliacea
No full text
Evidence of regional differences in the lectin histochemistry along the ductus epididymis of the lizard, Podarcis sicula Raf
No full textThe regional difference in the carbohydrate components of the ductus epididymis epithelium of a lizard was delineated
by means of 13 lectins. Basal cells expressed only N-acetylglucosamine (GlcNAc). Throughout the ductus, the secretory
cells showed oligosaccharides with terminal N-acetylneuraminic acid (Neu5Ac)α(2,6)galactose (Gal)/N-acetylgalactosamine
(GalNAc) and internal mannose (Man) and/or glucose (Glc) in the whole cytoplasm, oligosaccharides terminating in
Neu5Acα(2,6)Galβ(1,3)GalNAc, Neu5Acα(2,6)Galβ(1,4)GlcNAc, GalNAc, GlcNAc, and fucose (Fuc) in the supra-nuclear
zone, and also glycans terminating in Neu5Acα(2,3)Galβ(1,4)GlcNAc, Neu5Acα(2,6)Galβ(1,3)GalNAc, Galβ(1,4)GlcNAc
on the luminal surface. In the caput and corpus regions, the supra-nuclear cytoplasm was characterized by terminal
Galβ(1,4)GlcNAc and αGalNAc, the luminal surface by αGalNAc and Gal. The Golgi zone, showing oligosaccharides with
terminal Neu5Acα(2,3)Galβ(1,4)GlcNAc, Neu5Acα(2,6)Galβ(1,3)GalNAc, Neu5Acα(2,6)Galβ(1,4)GlcNAc, and internal
GlcNAc, expressed terminal Galβ(1,4)GlcNAc and αGalNAc in the caput, and terminal βGalNAc in the corpus. The granules
showed all the investigated carbohydrates in their peripheral zone except terminal βGalNAc and Fuc, whereas internal Man/Glc
and terminal Gal were expressed in the central core, and Fuc throughout the ductus, terminal GlcNAc in the caput and corpus,
and terminal αGalNAc only in the corpus
Recensione a: M. Labate, Petronio. Ricostruzioni e interpretazioni, a cura di G. Vannini e G. Zago, Pisa, Edizioni della Normale, 2020, p. 286
No full textReview of the collected studies on Petronius Satyricon by M. Labate
Testicular activity and sperm glycoproteins in giant red shrimp Aristaeomorpha foliacea
No full textThe reproduction of male giani red shrimp Aristaeomorpha foliacea, collected from thè late
winterto thè summer in thè north-western lonian Sea (Mediterranean Sea), was investigated using
histological and histochemistry methods. Seasonal changes in thè spermiogenesis and thè glycoprotein
pattern were found and sperm glycoproteins matured as gametes moved from thè testis to
thè terminal ampliila. In serial sections stained with hematoxylin and eosin thè testicular activity
appeared to be discontinuous. In late winter thè testes had no meiotic activity and thè seminiferous
epithelium consisted of interkinetic spermatogonia and spermatozoa. In spring, spermiogenetic
activity was high and thè seminiferous epithelium mainly consisted of spermatocytes and spermatozoa
while in summer, thè testes were again inactive since both spermatocytes and spermatozoa
were lacking. The use of twelve different lectins indicated that thè intratesticular spermatozoa
from late winter to summer contain surface binding sites for SNA, MAA, Con A and KOH-sialidase
(si)-WGA. In March and July they also exhibited nuclear and cytoplasmic reactivity for SNA and
Con A. In thè hemispermatophore thè spermatozoa displayed a more complex lectin-binding pattern
because they also reacted with PNA, DBA, HPA, OSA II. The staining with DBA, KOH-si-
DBA, and OSA II showed differences between thè spermatozoa from late winter-spring
hemispermatophores and summer hemispermatophores: thè former showed a nuclear affinity
whereas thè latter displayed surface and/or cytoplasm staining. No reaction was observed with
SBA, GSAI-B4, UEA I, and LTA
IMMUNOHISTCHEMICAL EVIDENCE OF SEASONAL CHANGES OF GONADOTROPES IN MALE RUIN LIZARD(PODARCIS SICULA CAMPESTRIS DE BETTA)
No full textTThe pars distalis from the pituitary gland of adult male ruin lizards (Podarcis sicula campestris De Betta), captured during the reproductive period (May and June), was studied immunohistochemically using specific antibodies against hFSHβ, hLHβ and oLHβ with the avidin-biotin-peroxidase complex (ABC) procedure to determine the localization of both gonadotropins The immunostaining with anti-hFSHβ and anti-hLHβ allowed identification of morphologically distinct FSH containing cells and LH containing cells, whereas anti-oLHβ serum showed cross-reactivity with cells immunostained with the anti-hFSHβ and anti-hLHβ sera. The gonadotropic cells took up approximatively 10.5% of the area of the pars distalis: 10% was positive for FSH, whereas only 0.5% was positive for LH. The FSH cells were distributed throughout the pars distalis, whereas the LH cells were only located in the rostral region. Double-immunostaining procedure did not reveal cells containing both gonadotropic hormones. The findings indicate that FSH and LH are produced in separate pituitary cells
Notula: 279. Persicaria capitata (Polygonaceae). In: Galasso G., Nepi G., Domina G., Peruzzi L. (eds.), Notulae alla flora esotica d'Italia: 12
No full textAbstract non disponibil
A histochemical and ultrastructural study of oogenesis of Aristaeomorpha foliacea (Risso, 1827)
No full textOvaries from mature giant red shrimp Aristaeomorpha foliacea were investigated histochemically and ultrastructurally.
Four growing stages of the oocytes were distinguished: premeiosis stage, previtellogenetic stage, early
vitellogenic stage and late vitellogenic stage. In addition, occasional resorptive oocytes were found. Oogonia and
premeiotic oocytes were found in germinative zones. Previtellogenic and vitellogenic oocytes were localized in
maturative zones. As vitellogenesis proceeded, oocytes showed a progressive development in the number of lipid
droplets as well as in the extension of RER, constituted of dilated cisternae, uniformely scattered throughout the
cytoplasm. The RER produced yolk granules and a lampbrush-like substance. The latter was released under the oolemma
and constituted a characteristic cortical zone. The oolemma did not develop microvilli or micropinocytotic
vesicles to incorporate yolk precursors. Thus, the protein yolk appeared to be of endogenous origin. Few somatic
cells were found around the oocytes, but they never gave place to a continuous epithelial layer around oocytes, thus
it is not possible to speak of ovarian follicle. The cytoplasm of these mesodermal-oocyte associated cells (MOAC)
was characterized by a typical steroidogenic apparatus. Few resorptive immature oocytes were found inside late
vitellogenic oocytes. Since the ovaries were packed with late vitellogenic oocytes and the few immature oocytes
were hardly detectable, oocyte maturation occurred in a synchronous way
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