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Biomedical subjects

P Soldani

Publications and source records attributed to P Soldani.

At least 55 records · Page 3Linked to original sources
PubMed1990

Adrenergic innervation of the ductus deferens in young and aging rats: a morpho-functional investigation.

The pattern of adrenergic innervation and the responsiveness to alpha-agonists of the epididymal and prostatic portions of the ductus deferens from young and aging rats were examined. The histochemical pictures showed that the distribution of the adrenergic fibres varies between the 2 ends of the ductus deferens, with a greater density in the prostatic portion. Tissues from rats aged 20 months showed the same difference in the adrenergic pattern between the 2 portions. Generally, the fluorescent bundles from the tissues of senescent animals seemed to be more numerous and compact. The functional data appear to be in contrast with the morphological observations, because the epididymal tract of young rats showed the highest responsiveness to alpha-agonists. An inverse correlation between the number of adrenergic fibres and receptor responsiveness is hypothesized.

Adrenergic alpha-Agonists↗
PubMed1989

A monoclonal antibody to a synthetic fragment of rabies virus glycoprotein binds ligands of the nicotinic cholinergic receptor.

Rabies virus glycoprotein and snake venom curaremimetic neurotoxins share a region of high homology (30-45 for neurotoxins and 190-203 for the glycoprotein) in the regions that are believed to be responsible for binding the nicotinic acetylcholine receptor. Monoclonal antibodies raised to the 190-203 synthetic fragment of rabies virus glycoprotein were immobilized on a high performance affinity chromatography column and were able to bind neurotoxins. Toxins were displaced from the affinity column by elution at acidic pH and by affinity competition with acetylcholine at neutral pH. Furthermore, the affinity column proved to be useful for the purification of cholinergic ligands. Overall, these results indicate that the paratope of our monoclonal antibodies could behave as an 'internal image' of the nicotinic cholinergic receptor acetylcholine binding site.

Amino Acid Sequence↗
PubMed1989

Adrenergic pattern of aorta and superior mesenteric arteries in young and senescent rats.

The noradrenergic innervation of two portions of the aorta (thoracic and abdominal) was studied by the fluorescence method in rats belonging to two different age groups (3 and 28 months). Adrenergic fibres were clearly visible only in the abdominal tract of the aorta, and appeared to be more distinct and more numerous in young rats compared with the older ones. By contrast, the superior mesenteric artery was regularly found to possess a rich adrenergic plexus, even if catecholamines were more densely present in younger animals.

Adrenergic Fibers↗
PubMed1988

High performance liquid chromatography immunoaffinity purification of antibodies and antibody fragments.

A rapid antibody purification method is described which combines high performance liquid chromatography (HPLC) resolution with affinity chromatography specificity. The antigen used as immobilized ligand is bound to the HPLC column matrix by reacting the amino groups of the protein with the active epoxy groups of the latter. Once the reaction has finished, the unreacted groups of the column are saturated with an appropriate scavenger. Unrelated proteins are then washed out and the specific antibodies recovered by lowering the pH of the elution buffer.

Animals↗
PubMed1988

Antipeptide monoclonal antibodies inhibit the binding of rabies virus glycoprotein and alpha-bungarotoxin to the nicotinic acetylcholine receptor.

It has been reported that binding to muscle nicotinic acetylcholine receptor at the post-synaptic membrane is an important event of the rabies virus neurotropism. The binding site can be located within the 190-203 region of the virus glycoprotein sharing a high degree of homology with the "toxic loop" of the curare-mimetic snake neurotoxins. We have synthesized a tetradecapeptide corresponding to this glycoprotein region and used it, following conjugation with an immunogenic carrier to raise MAbs. We found that some MAbs raised against the peptide were able to recognize both the virus glycoprotein and the snake neurotoxin alpha-bungarotoxin; moreover, they can inhibit the binding of rabies virus glycoprotein and alpha-bungarotoxin to the nicotinic acetylcholine receptor extracted from the electric organs of Torpedo marmorata. On the basis of this cross-reactivity, we suggest that rabies virus glycoprotein and curare-mimetic snake neurotoxins share three-dimensionally similar structures in order to bind to the nicotinic cholinergic receptor. The potential use of the immunogenic properties of the peptide for the rational design of a synthetic vaccine against rabies is proposed.

Antibodies, Monoclonal↗
PubMed1988

Age-related changes in the recovery of noradrenaline content in sympathetic fibres after reserpine treatment.

The aim of the present study was to evaluate noradrenaline recovery times in sympathetic fibres after reserpine administration by using fluorescence histochemical techniques. The spleen, the kidney, and the large intestine were examined 24 h to 15 d after reserpine treatment, in both young and aged male Sprague-Dawley rats, in order to establish not only the possible differences in recovery times of the various organs, but also if senescence can influence these times. The complete restoration of the noradrenaline content took place sooner in younger rats than in aged ones, and, within the same age-group, the recovery was quicker in the spleen and needed longer times in the large intestine, particularly in aged rats.

Aging↗
PubMed1987

Sperm-egg interaction in the mouse using live and glutaraldehyde-fixed eggs.

A study of interaction between gametes in the mouse, using live and glutaraldehyde-fixed eggs, showed that, while in live eggs the binding is a two-step process ("early" and "late" binding), the process is one step when the spermatozoa interact with fixed eggs. The second point that emerged from this study is that uncapacitated and capacitated spermatozoa bind the zonae pellucidae of live and fixed eggs in the same way, but only the capacitated spermatozoa bound to live eggs undergo a complete acrosome reaction and penetrate the zona pellucida. Moreover, it has been shown that binding to fixed eggs, just as to live eggs, is Ca2+-dependent, and it can be reversed by EGTA. Fixed eggs thus are a good model to study only one step of the sperm-egg interaction removed from all the other events of the fertilization process.

Animals↗
PubMed1986

Noradrenergic innervation of the lingual papillae in certain rodents pre-treated with adriblastin. I. Comparative study on the filiform and fungiform papillae.

A comparative study was carried out on the behaviour of the noradrenergic fibres of the filiform and fungiform papillae of four different species of laboratory animals. The adrenergic network proved to be less important in rats and mice than in guinea-pigs and rabbits; moreover, the extreme branchings proved to be more or less closely connected with the taste buds of the mice, guinea-pigs and rabbits. Hypotheses are advanced concerning the possible significance of adrenergic innervation of these lingual papillae.

Adrenergic Fibers↗
PubMed1984

Morphogenesis of 'decapitated' spermatozoa in a man.

Study of biopsy specimens of a man with 'decapitated' spermatozoa indicated that the malformation was due to an overproduction of a membraneous vesicles system by the Golgi complex in the region between the centrioles and acrosome during the spermatid stage. The tails were almost normal in structure and 50% were motile in the ejaculate although few followed a straight trajectory.

Adult↗
PubMed1984

Sperm morphogenesis, structure and function in humans over 70 years old.

Semen and testicular biopsy samples from different aged human donors have been examined for any age related changes in sperm morphogenesis, structure and function. Various abnormalities and defects, some being unique to spermatozoon of elderly men, were observed at the light and electron microscope levels. In spite of this, the best fractions of ejaculated spermatozoa population maintains his function, as demonstrated by some complete egg penetrations observed with the 'zona free' hamster egg test system.

Acrosome↗
PubMed1981

Scanning electron microscopy and human sperm pathology.

This paper has been carried out in order to inquire whether some of the best known human malformations can be recognized by scanning electron microscopy. The SEM appearance of "straight tailed", "empty tailed", "short tailed", "round headed", "double", "old" human spermatozoa is described, and related to the inner structure. Straight tails and empty tails are quite evident at SEM. These defects are due to severe axonemal defects, related to dynein and tubulin deficiencies: "9+0", "arm less" and "axoneme less" spermatozoa are included in this category. Short tails and round heads are still more evident defects, due to complete absence of tail structures or acrosome and easily recognizable at SEM. Double spermatozoa are consistently in patients having abnormally high prolactin level and SEM is obviously sufficient for the diagnosis. Finally, spermatozoa in aged individuals show in SEM a peculiar shape due to absence of immature stages, reduced cytoplasm, disordered axoneme. It is concluded that SEM examination is a good tool for the identification of most of the best known human sperm abnormalities.

Electrophoresis↗
PubMedDate not supplied

Ultrastructural localization of NADPH-diaphorase activity in the endothelial cells of human nasal respiratory mucosa.

The cavernous sinuses are the most peculiar feature of the nasal angioarchitecture, due to their ability to retain a large quantity of blood in reply to a variety of topical and systemic stimuli. Recently, nitric oxide (NO) has seemed to be crucially involved in the nasal vascular regulation. The distribution of NO-synthase (NOS), the enzyme that catalyzes the formation of NO, was studied in the endothelium of nasal blood vessels by the ultracytochemical detection of reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) enzymic activity. The endothelium of the cavernous sinuses appeared strongly positive, whereas the endothelium of arterioles was occasionally labeled. The endothelial cells of capillaries and venules were found to be NADPH-d negative. The strong enzymic activity observed in the cavernous sinuses suggests a major role of NO in the capacitance vessels compared to the resistance vessels. The hypothesis of a reciprocal inhibition between the NOS enzymic pathways present in the respiratory epithelium and in the endothelium of cavernous sinuses is put forward. The nasal disorders characterized by anomalous vasomotility and vascular permeability could be caused in part by the irregular control of these complex interactions.

Adolescent↗
PubMedDate not supplied

Ultrastructural and biochemical evidence of apoptosis induced by a novel inhibitor of protein geranylgeranylation in human MIA PaCa-2 pancreatic cancer cells.

Analogs of geranylgeranyl diphosphate (GGdP) have been demonstrated to inhibit the geranylgeranylation of proteins, producing cytotoxic activity in human prostate cancer cells. A detailed study is reported on the programmed cell death in vitro of human exocrine pancreas cancer cells (MIA PaCa-2) induced by the most active compound of this series of geranylgeranylation inhibitors, the dipotassium salt of (E,E,E)[2-oxo-2-[[(3,7,11,15-tetramethyl-2, 6,10,14-hexadecatetraenyl)-oxy]amino]ethyl] phosphonic acid (BAL 9504), using transmission and scanning electron microscopy (SEM). The results show that, after 72 h of treatment with BAL 9504, 25 microM, most MIA PaCa-2 cells display the typical morphological features of apoptosis, including condensation of nuclear chromatin, dilation of endoplasmic reticulum, and fragmentation of both nucleus and cytoplasm, giving rise to small membrane-bound vesicles (apoptotic bodies); surface protrusions and blebs are well demonstrated by SEM. The electrophoresis showed the presence of various bands corresponding to fragmented DNA of 180 base pairs, or multiples of this length, thus indicating that BAL 9504 effectively induces apoptosis. The present study provides the first evidence that inhibition of protein geranylgeranylation produces apoptosis in human MIA PaCa-2 exocrine pancreas cancer cells.

Apoptosis↗
PubMedDate not supplied

Morphohistochemical characterization of suramin--induced chronic toxicity in rat kidney.

The effects of a chronic administration of suramin were evaluated on renal parenchyma of young rats. Animals were given suramin 18 mg/kg i.p. twice a week for two months, a treatment schedule equivalent to that used in cancer patients. At the end of the treatment, suramin concentrations in plasma and kidney were assayed and a morphohistochemical examination of renal parenchyma was carried out. Marked and widespread alterations were detected in both cortex and medulla and were associated with elevated tissue suramin levels exceeding 5 mg/g of tissue. The present data demonstrate that suramin induces a severe chronic renal damage in the rat, associated with high drug tissue levels.

Animals↗
PubMedDate not supplied

Effect of reserpine and calcium antagonists on doxorubicin storage in various organs of young and senescent rats.

Reserpine pre-treatment causes a considerable decrease in typical red-orange doxorubicin fluorescence of the organs examined (kidney, large intestine, spleen) and a similar picture is observed after calcium antagonists administration. This effect is far more evident in the spleen and large intestine than in the kidney; moreover, it seems more marked in young rats compared with aged ones. An inhibitory action of these drugs on the anthracycline transport carrier through the cell membrane is hypothesized.

Aging↗