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F Ciani

Publications and source records attributed to F Ciani.

At least 55 records · Page 3Linked to original sources
PubMed1991

Lectin histochemical study of olfactory neurons in the eel.

Lectin histochemical studies were performed on paraffin embedded sections of the olfactory system of the eel to identify specific glycoconjugates on the surface of primary olfactory neurons. The olfactory receptors, the olfactory nerve fibres and their terminals in the bulbs were labelled with the lectins (SBA, BSA-I, BSA-I-B4 and DBA) HRP-conjugated or biotinylated. The lectin staining patterns indicate that the membrane of olfactory neurons of the eel had oligosaccharides with alpha-galactose and alpha-N-acetyl-D-galactosamine residues. These findings represent the demonstration of a molecular probe that recognizes specific sets of neurons. The identical histochemical features previously described in the olfactory neurons in amphibians suggest that these carbohydrate moieties might to related to modulation of the cell-cell interactions in the olfactory system of vertebrates.

Anguilla↗
PubMed1990

The beneficial effect of atrial natriuretic peptide on cyclosporine nephrotoxicity.

Nephrotoxicity is the most common and important side effect of cyclosporine (CyA) therapy. It is characterized by a fall in glomerular filtration rate (GFR) and by a decrease in sodium and water excretion. Since atrial natriuretic peptide (ANP) has been shown to increase GFR and to cause a potent diuretic and natriuretic effect, we have investigated the potential beneficial action of ANP on CyA induced renal injury. To this end two groups of animals were studied: 1) rats that received an intravenous infusion of CyA (20 mg/kg body weight) (acute studies) and 2) rats that have been treated with daily intraperitoneal injections of CyA (20 mg/kg body weight) for a total of seven days (chronic studies). To both groups of rats synthetic ANP was administered intravenously as a bolus (10 micrograms/kg) and then as a constant infusion (1 microgram/kg/min). In group 1 the CyA administration resulted in a decrease in GFR, urine output, urinary sodium and potassium excretion. After ANP infusion there was a prompt restoration of GFR, with a large rise in urine, sodium and potassium excretion rates. Similar effects on renal hemodynamics and electrolyte excretion rates were detected after ANP administration in chronic CyA treatment. These data show that the administration of ANP to rats that have been exposed to acute or chronic CyA treatment is able to reverse the harmful effect of CyA on renal function.

Acute Kidney Injury↗
PubMed1990

Mitotic activity of the telencephalic matrix areas following optic tectum or pallial cortex lesion in newt.

The telencephalic proliferative response has been studied in adult newts after lesion on the central nervous system. Both in the animals injured on the optic tectum and in those on the telencephalon a telencephalic proliferative response was observed, localized in the dorsal pallial areas and in the striatum. Quantitative analysis of the proliferative activity of the matrix cells present in the telencephalon showed a different response pattern. In the animals lesioned on the telencephalon the labelled cells are much more numerous in the injured hemisphere than in the healthy one and these cells persists at a high level even in the specimens fixed 90 days after the lesion. In this case no labelled cells are observed in the midbrain. The number of labelled cells in the animals lesioned on the optic tectum was identical in both telencephalic hemispheres; this number decreases from 15 to 30 days after the injury and at 90 days labelled cells are not observed. These data confirm the presence of a neuronotrophic factor released in the ependymal fluid and active on the telencephalic periventricular matrix cells but not on the undifferentiated cells of the grey layers of the optic tectum. It is also assumed that the proliferation of matrix cells of an injured area causes the formation of glial cells and neurons, such proliferation in an intact zone is oriented to differentiation of glial cells alone.

Animals↗
PubMed1990

Proliferative response of the mesencephalic matrix areas in the reparation of the optic tectum of Triturus cristatus carnifex.

The localization and proliferative response of optic tectum matrix cells has been studied in adult newt following an experimental lesion on an optic lobe. The results show that 15 days after the lesion the cells in division, autoradiographically labelled, are located in the periventricular layer. Thirty days after the lesion the labelled cells are also found in the innermost grey layers; at 90 days the injured optic tectum regains the cytoarchitecture characteristic of this centre, with labelled cells, whether in the external or in the internal pyriform layers. In all the stages the labelled cells are also found in the periventricular layers of the controlateral optic tectum, in the dorsal pallium and in the striatum. The quantitative data exhibit the existence of a direct relationship between the number of proliferating cells in the injured optic lobe and the extent of the lesion. These data show the possibility of active cellular proliferation for the reconstruction of the lesioned nervous area and for restoration of the characteristic histological structure.

Animals↗
PubMed1989

Cytochemical localization of alkaline phosphatase and Na+, K+-ATPase activities in the blood-brain barrier of Rana esculenta.

The ultrastructural distribution of alkaline phosphatase and Na+, K+-ATPase on the brain capillaries in Rana esculenta was investigated. Alkaline phosphatase activity appears both on the luminal and abluminal walls of the endothelial capillary cells; Na+, K+-ATPase is, instead, only present on the abluminal side. This different enzymatic distribution indicates that endothelial cells of the brain capillaries are polarized and the luminal and abluminal endothelial membranes are functionally different. The role of these two enzymatic activities is discussed in relation to the blood-brain barrier.

Alkaline Phosphatase↗
PubMed1989

Ultrastructural localization of acetylcholinesterase in Axolotl brain capillaries.

The ultrastructural distribution of cholinesterases on the brain capillaries of Axolotl has been studied. The Axolotl brain contains branching, Anastomosing capillary network and capillary loops. The presence of acetylcholinesterases is seen on the basal lamina and in the spaces between the endothelial cells and the pericytes of both types of vessels. The role of this enzyme in the blood-brain barrier is discussed.

Acetylcholinesterase↗
PubMed1988

Opening of blood-brain barrier in Triturus cristatus carnifex by hyperosmolar mannitol solutions.

The permeability of the newt cerebral capillaries to lanthanum ion has been studied after perfusion with mannitol solutions of increasing molarity. In the control specimens lanthanum deposits were limited to the luminal side of the capillaries and tracer did not spread to the pericapillary spaces due to the tight junctions. Treatment with hypertonic solutions of mannitol (0.25M, 0.5M, 1M) caused opening of the blood brain barrier with a progressive increase in lanthanum between the endothelial cell edges, in the basal lamina and in the extracellular spaces of the nervous parenchyma in relation to the molarity of the mannitol solution. The spread of lanthanum is probably due to opening of the tight junctions between the endothelial cells, since pinocytotic vesicles labelled with tracer were not evident.

Animals↗
PubMed1988

Histochemical and biochemical study on the acetylcholinesterase and choline acetyltransferase in the brain and spinal cord of frog, Rana esculenta.

The histochemical distribution of acetylcholinesterase (AChE) activity in the brain and spinal cord of Rana esculenta, has been studied. Moreover the levels of choline acetyl-transferase (ChAT) and of AChE, have been determined biochemically in different regions of the central nervous system. The results obtained from combining the histochemical and biochemical analyses allowed us to obtain more significant information on the localization of cholinergic neurons and the projection areas of the cholinergic terminals.

Acetylcholinesterase↗
PubMed1987

Ultrastructural analysis and cholinesterase activity in the brain capillaries of Bufo bufo and Rana esculenta.

We have investigated the structure and the cholinesterase features of the brain capillaries in two adult Amphibians (Rana esculenta and Bufo bufo). We found that brain capillaries are un-fenestrated and the endothelial cell edges are joined by tight junctions. The brain capillaries in both species are characterized by high levels of AChE. This enzyme is only localized in the basal membrane, whereas we have found the reaction product neither in the endoplasmatic reticulum nor in the Golgi apparatus. On the contrary the brain capillaries are deprived of BuChE. Only in one experiment traces of reaction product were found. The significance of this datum and the non-nervous role of cholinesterase is discussed.

Acetylcholinesterase↗
PubMed1987

Newly-formed neurons in the regenerating optic tectum of Triturus cristatus carnifex.

A histochemical light and electron microscopy study of acetylcholinesterase (AChE) was carried out on the regenerating opic tectum of adult newt. A plug of optic tectum was removed and 15 days later [6-H3] thymidine was injected. Ninety days after the lesion the brain was removed, treated for histochemical AChE-detection and autoradiographic analysis. This double treatment showed the capacity of these adult amphibians to regenerate the nervous tissue through the proliferation of undifferentiated elements and their subsequent differentiation into neurons as is shown by the presence of cells both labelled by [6-H3] thymidine and by the AChE-reaction product.

Acetylcholinesterase↗
PubMed1986

[Recurrent alveolitis caused by amiodarone].

More recently a few cases of pulmonary toxicity due to amiodarone administration and reversed following drug discontinuation and corticosteroid therapy have been reported. An unusual case of recurrence of amiodarone pulmonary toxicity is described. After receiving amiodarone 1.200 mg/week for 6 month a 54-year-old woman showed clear signs of pulmonary alveolitis with ray signs of diffuse pulmonary infiltrates. The pulmonary symptoms recurred after discontinuing corticosteroidis 17 months after amiodarone was stopped and were associated with a persistent amiodarone level in broncho alveolar lavage. Only after 20 months the complete resolution of pulmonary symptoms was achieved.

Amiodarone↗
PubMed1986

Labelled neurons in mesencephalon and medulla oblongata of newt after periocular injection of horseradish peroxidase.

The retrograde transport of HRP after periocular space injection was investigated in mesencephalon and medulla oblongata of newt brain. In the tegmentum the neurons of oculomotor and troclear nucleus are filled. In the optic tectum some filled cells of mesencephalic trigeminal nucleus were, for the first time, described. This suggest that these neurons are deputated to proprioceptive innervation of the extrinsic ocular muscles. In the medulla oblongata the labelled neurons were located in the ganglion of Gasser and in the sensitive column of the trigeminal area. Other labelled neurons were found in the abducent nucleus and in the visceromotor column of the facial nerve. The authors discuss the analogy between the trigeminal labelled neurons of the medulla oblongata with supratrigeminal nucleus of the mammals.

Animals↗
PubMed1984

Cytochemical localization of alkaline phosphatase and ouabain-sensitive K+-dependent p-nitrophenylphosphatase activities in brain capillaries of the newt.

The ultrastructural localization of alkaline phosphatase and K+-NPPase was investigated in brain capillaries of newt by a cytochemical study using whole brain perfusion. The alkaline phosphatase activity was present in both luminal and antiluminal membranes of the endothelial cells. By contrast, the K+-NPPase was located only in antiluminal membranes of the brain capillaries. This distinct enzymatic distribution suggested that the luminal and antiluminal membranes are functionally different. The role of alkaline phosphatase and K+-NPPase in the blood brain barrier is discussed.

4-Nitrophenylphosphatase↗
PubMed1984

Matrix area activity in the regenerating optic tectum of Rana esculenta.

After keeping specimens of Rana esculenta at 4 degrees C for 24 hrs., the Authors removed a plug of right optic tectum. Thirty days later they injected 6-H3 thymidine and on the 200th day after surgery sacrificed the animals. With this technique it is possible to show the high regenerative capacity of the optic tectum; in fact, it is possible to observe reconstruction of the typical cellular and fibre layers of the removed nervous area. The origin of the cellular elements which supported this regenerative process and the possible connection between these results and restoration of the hemotrophic embryonic conditions due to absence of the blood-brain barrier, consequent on the cold treatment, is discussed.

Animals↗
PubMed1984

Ultrastructural study and cholinesterase activity of paired capillaries in the newt brain.

We have investigated the ultrastructural and histochemical (AChE and BuChE) features of intracerebral vessels in newt. The blood vessels of the newt brain are paired and end in a closed loop. The two limbs, each of them has delineate the lumen by one endothelial cell, are enclosed within a single basement membrane and are separated from each other by a thin intercapillary wall. The brain capillaries are un-fenestrated and the overlapping endothelial cells were connected by clefts. Ependymal astrocytes extensively ensheath the surface of brain capillaries, but the sheats are incomplete. Pericytes and mast cells are frequently sandwiched in the endothelial basal lamina. Microglial cells are also present adjacent to cerebral vessels. The newt cerebral capillaries are characterized by high levels of AChE. This enzyme is localized in the basal membrane and in extracellular spaces between the overlapping endothelial cells. The vascular walls are instead deprived of BuChE activity. The non-nervous role of cholinesterases is discussed.

Acetylcholinesterase↗