Search results for "Testis"
showing 10 items of 107 documents
Day/night changes of pineal gland volume and pinealocyte nuclear size assessed over 10 consecutive days
1984
Previous studies aimed at elucidating day/night changes of pineal gland size and pinealocyte nuclear volume have yielded contradictory results. The aim of the present investigation was to examine the above parameters over a period of 10 successive days, at 6-hour intervals under a lighting regimen of LD 12:12 (7 a.m. to 7 p.m.). It was found that changes in pineal gland volume could not be correlated with the light/dark phases; instead, a rhythm with a two-day period was encountered. Pinealocyte nuclear volume, by contrast, showed clear circadian changes, exhibiting troughs during photophase and peaks during scotophase. In this experimental series, the karyometric results conformed to the m…
Regeneration of the testes in the clawed toad (Discoglossus pictus Otth.) after complete surgical removal
1967
Dopo ablazione totale dei testicoli inDiscoglossus pictus si ha rigenerazione. Nei testicoli rigenerati si riscontrano spermatociti in tutti gli stadi di sviluppo e talvolta anche spermi. E avanzata l'ipotesi che la rigenerazione avvenga a partire da cellule somatiche degli spermidutti.
Virus-like particles, bacteria and microsporidia affect spindle-associated membranes in spermatocytes of Lepidoptera species.
1997
SummaryLarval testes of four Lepidoptera species were examined using electron microscopy. The testes of one species, the Mediterranean mealmothEphestia kuehniella(Pyralidae), were devoid of intracellular pathogens and serve as a control. In this species, metaphase spindles of primary spermatocytes showed a thick layer of perispindle membranes. The membranes were structurally very similar to the agranular endoplasmic reticulum. Membranes of this type occurred also at high frequency throughout the spindle matrix. The analysis of larval testes ofPieris brassicae(Pieridae) revealed virus-like particles within spermatocytes. In another species,Philudoria potatoria(Lasiocampidae), the spermatocyt…
Structural characterization and primary in vitro cell culture of locust male germline stem cells and their niche
2011
AbstractThe establishment of in vitro culture systems to expand stem cells and to elucidate the niche/stem cell interaction is among the most sought-after culture systems of our time. To further investigate niche/stem cell interactions, we evaluated in vitro cultures of isolated intact male germline–niche complexes (i.e., apical complexes), complexes with empty niche spaces, and completely empty niches (i.e., isolated apical cells) from the testes of Locusta migratoria and the interaction of these complexes with isolated germline stem cells, spermatogonia (of transit-amplifying stages), cyst progenitor cells, cyst progenitor cell-like cells, cyst cells, and follicle envelope cells. The stru…
Sexual size dimorphism predicts rates of sequence evolution of SPerm Adhesion Molecule 1 (SPAM1, also PH-20) in monkeys, but not in hominoids (apes i…
2010
Based on a dataset comprising coding DNA sequences of 23 anthropoid primates, we herein investigate if rates of sequence evolution of SPerm Adhesion Molecule 1 (SPAM1, also PH-20), which participates in sperm–egg interaction, is lower in more sexually dimorphic species. For comparison, we analyze sequence evolution of apolipoprotein A-IV (APOA4) and apolipoprotein A-V (APOA5), which should evolve under less or even no sexual selection given their expression in blood, digestive tract, liver, and lungs. Regression analyses provides significant support for a negative dependence of SPAM1 derived branch-specific ratios of non-synonymous to synonymous substitution rates (dN/dS) on sexual size dim…
Androglobin: a chimeric globin in metazoans that is preferentially expressed in mammalian testes
2012
Abstract: Comparative genomic studies have led to the recent identification of several novel globin types in the Metazoa. They have revealed a surprising evolutionary diversity of functions beyond the familiar O2 supply roles of hemoglobin and myoglobin. Here we report the discovery of a hitherto unrecognized family of proteins with a unique modular architecture, possessing an N-terminal calpain-like domain, an internal, circular permuted globin domain, and an IQ calmodulin-binding motif. Putative orthologs are present in the genomes of many metazoan taxa, including vertebrates. The calpain-like region is homologous to the catalytic domain II of the large subunit of human calpain-7. The glo…
Sonographic appearances of the postoperative testis
2015
Purpose: To describe the sonographic findings observed in the testis in patients who have undergone testicle-sparing surgery and surgical biopsies. Methods: We reviewed the color Doppler sonographic findings from 14 patients after testicular interventions: 2 open biopsy procedures for infertility and 12 testicle-sparing surgical procedures (1 for spontaneous intratesticular hemorrhage and 11 for small tumors). Ten patients had benign tumors; one had a malignancy. Three patients were symptomatic; all others were studied as follow-up. Results: Hypoechoic and hypovascular lesions at site of surgery were seen in 10 of the 11 patients after tumorectomy; no changes were observed in one patient. T…
Nucleoside phosphotransferase in animal tissues. Tissue distribution and kinetic properties
1985
Amphibian, avian and mammal tissues contain a nucleoside phosphotransferase clearly different from those previously described in vegetables and bacteria. Whatever the animal source, the enzyme showed many similar characteristics as far as substrate specificity, dependence upon Mg2+, instability at 37 degrees C, and the protecting effect of nucleotides were concerned. Moreover, when submitted to gel filtration, the enzyme behaved in all cases as a dissociable high molecular weight protein, whose degree of association was controlled by nucleotides. In amphibian and avian tissues multiple forms of the enzyme seem to be present which differ for the substrate concentration at half-maximal veloci…
[Cystic dysplasia of rete testis associated with ipsilateral renal agenesis. Case report].
2003
Cystic dysplasia of the rete testis is a rare abnormality often associated with the ipsilateral agenesis of kidney. This malformation is due to a development defect of the mesonephric duct which is the cause of both the dilation of the testicular rete testis and renal agenesis. A case of this rare malformation, showing all the peculiarities described in the medical literature, is presented. A 3 years-4 months boy was examined for an asymptomatic left scrotal mass; thus, he underwent ultrasonography, which showed a multiple tubular and cystic dilatation of left rete testis, associated with the absence of left kidney, afterward confirmed by MAG3-radionuclide scan. Diagnosis was also validated…
Plasma membrane Ca2+ ATPase 4 is required for sperm motility and male fertility.
2004
Calcium and Ca(2+)-dependent signals play a crucial role in sperm motility and mammalian fertilization, but the molecules and mechanisms underlying these Ca(2+)-dependent pathways are incompletely understood. Here we show that homozygous male mice with a targeted gene deletion of isoform 4 of the plasma membrane calcium/calmodulin-dependent calcium ATPase (PMCA), which is highly enriched in the sperm tail, are infertile due to severely impaired sperm motility. Furthermore, the PMCA inhibitor 5-(and-6)-carboxyeosin diacetate succinimidyl ester reduced sperm motility in wild-type animals, thus mimicking the effects of PMCA4 deficiency on sperm motility and supporting the hypothesis of a pivot…