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N Pescosolido

Publications and source records attributed to N Pescosolido.

At least 19 recordsLinked to original sources
PubMed2003

An NMR spectroscopy study of bendaline-albumin interactions.

The complete assignment of the 1H and 13C NMR spectra of bendaline (BNDL) was performed by mono-dimensional and homo- and hetero-correlated two-dimensional NMR experiments. The interaction between bendaline and albumin was also studied by the analysis of the motional parameters spin-lattice relaxation times, allowing the motional state of the BNDL free and bound with albumin to be defined. In absence of albumin the indazolacetic and benzylic moieties are characterized by roughly the same mobility and by positive sigma (cross-relaxation rates) values. In the presence of the macromolecule, the indazolacetic and benzylic moieties and the lysine change their motional behaviour to different extents, as indicated by correlation times. Data obtained in absence and in presence of the protein show that the molecular moiety of the bendaline most involved in the binding with albumin is the fragment H-4 H-5. The binding constant was evaluated at 2.4x10(3)M(-1).

Binding Sites↗
PubMed2003

Age-related changes in rat optic nerve: morphological studies.

Age-related changes of the optic nerve were studied in 3-month-old (young), 12-month-old (adult) and 24-month-old (aged) male Sprague-Dawley rats. Cross sections of the intracranial portion of the optic nerves of animals of different age groups were stained with haematoxylin-eosin and examined under a light microscope at low and high magnification. Other sections were stained with crystal violet for demonstration of glial cells. A third group of sections were stained immunohistochemically to detect glial fibrillary acidic protein (GFAP) which is a marker for localizing and characterizing astrocytes. All morphological results were subjected to the quantitative analysis of images and to statistical analysis to identify significant morphometrical data. Tissue protein concentrations were determined on homogenized fragments of optic nerve. Our results demonstrate the following age-related changes: (1) increase of the optic nerve sheaths (meningeal membranes); (2) increased number of astrocytes; (3) increase of areal density of GFAP immunoreactivity; (4) increased diameter and area of the optic nerve; (5) decreased number of nerve fibres; (6) decreased-size of nerve fibres and (7) decrease of the nerve fibres/meningeal membrane ratio from 3:1 to 1:1. Moreover, the protein amount does not change with age. The rat optic nerve, therefore, appears sensitive to ageing processes and can be considered as a useful model for the studies on neuronal ageing.

Aging↗
PubMed2001

Occurrence of catecholaminergic nerve fibers in the human uveoscleral tissue in conditions of normal and raised intraocular pressure.

The distribution of catecholaminergic nerve fibers (CNF) in human uveoscleral tissue was studied in six human eyes with normal intraocular pressure and in five eyes with increased pressure. The eyes with increased pressure had no visual field alterations and the patients did not have any glaucoma-related optic neuropathies. The amount of norepinephrine in these structures was also analysed. Catecholaminergic nerve fibers were detected by means of fluorescence microscopy and were counted using the quantitative analysis of images. Our results demonstrate that the occurrence of catecholaminergic nerve fibers (expressed in Conventional Units = C.U.) in human uveoscleral tissue is 15.4 +/- 1.6 C.U. in eyes with normal intraocular pressure. In eyes with increased intraocular pressure, these values were 12.2 +/- 1.2 C.U. Moreover, the amount of norepinephrine in tissue homogenates of the same eyes was evaluated and found to be 21.7 +/- 1.3 microg/gr tissue fresh weight of the human uveoscleral tissue in eyes with normal intraocular pressure. This value decreased to 18.8 +/- 1.1 microg/gr tissue fresh weight in the same tissue in conditions of raised intraocular pressure. In these experiments, the small number of eyes examined made it difficult to draw general conclusions. However, the role of human uveoscleral tissue was emphasized by the rich catecholaminergic innervation. A decrease of catecholaminergic nerve fibers and norepinephrine occurs when intraocular pressure is elevated. The modifications of these parameters, involved in the sympathetic control of aqueous humor outflow, may support the hypothesis of a possible relevant role for the human uveoscleral tissue in different pathological conditions.

Adult↗
PubMed2001

A murine cell culture model for post-trabeculectomy anfibrotic treatment: Induction of apoptosis by Cyclosporin.

PURPOSE: Experimental trials aimed at the research of selective antifibrotic agents are under development for the alternative treatment of glaucoma patients who are usually considered high-risk post-surgical individuals after trabeculectomy. Authors present here an in vitro model system for the treatment of post-trabeculectomy patients. The study is aimed at the evaluation of different drugs in a mouse fibroblast model. METHODS: The antifibrotic activity of Cyclosporin A, Interferon 2alpha, 5-Fluorouracyl was investigated on 3T6 cells in culture. Cell viability and proliferation was assessed after drug treatment. Molecular analysis of DNA degradation was evaluated by means of radioactive labeling and gel electrophoresis. RESULTS: The three drugs were shown to affect cell proliferation and viability in a differential fashion. However, only Cyclosporin A was able to control cell proliferation, inducing apoptosis. This phenomenon was reduced by supplementation of trolox, a compound known to inhibit programmed cell death. These results strongly suggest that this model system might be useful as a test of pharmacological functionality. CONCLUSION: A rapid and efficient model system is described for the assessment of cell viability and proliferation after treatment with agents of potential pharmacological use. Cyclosporin A induces a significant apoptosis. This is important for the negative control of fibrotic degeneration in post-trabeculectomy that is required for successful surgery in glaucoma patients. Therefore, Cyclosporin A might become a clinically interesting drug for the antifibrotic treatment of post-trabeculectomy.

3T3 Cells↗
PubMed2000

Distribution of peptidergic nerve fibres in the guinea pig trabecular meshwork.

A quantitative analysis of peptidergic nerve fibres located in the trabecular meshwork of the guinea pig has been performed. Our results confirm that this structure contains VIP-, NPY- and substance P-like immunoreactivity as major neurotransmitters. These findings were obtained using immunohistochemical techniques. For this purpose serial sections of the eye were stained by immunohistochemistry for each of three neurotransmitters and stained sections were analysed by quantitative image analysis. Our findings demonstrate that SP-positive, NPY-positive and VIP-positive nerve fibres occupy 11.2, 4.9 and 2.4%, respectively, of the observed area (expressed as conventional units, C.U.) in the trabecular meshwork of the guinea pig eye. It is relevant to emphasize that the area containing these three types of peptidergic nerve fibres appears to be large (18.5 +/- 6.6 C.U.) in proportion to the total observed area. The innervation of the drainage angle of the guinea pig eye has been well described by many authors. This is the first study to report quantitative measurements of three types of peptidergic nerve fibres identified and measured in this area. The presence of these three neurotransmitters in the trabecular meshwork of guinea pig eye suggests their possible participation in aqueous humor regulation.

Animals↗
PubMed2000

Microfilaments in regenerating cells of rabbit cornea: immunological and ultrastructural observations.

The role of myosin-like protein in regenerating and proliferating corneal cells following a standard alkali-injury in the rabbit eye has been studied. Microfilaments were observed by conventional transmission electron microscopy (T.E.M.) in injured epithelium and in fibroblasts. Typical microfilament bundles with electron dense structures and with stress fibers were evident. The presence of myosin-like proteins was demonstrated by means of immunochemical and autoradiographical techniques. Both epithelial cells and fibroblasts bind antimyosin-like antibodies (AMA). The same cells studied with the E.M. showed bundles of microfilaments in the cortical areas of their cytoplasm in correspondence with the same side of fluorescent or labelled AMA. The immunochemical and ultrastructural results suggest that both cells are able to produce in vivo movements involved in morphogenetic phenomena. Therefore, these structures play a role in post-traumatic corneal regeneration.

Actin Cytoskeleton↗
PubMed2000

Experimental ocular acute hypertension-induced chromatinic alterations in astrocytic cells in rat optic nerve.

The effects of ocular acute hypertension experimentally induced on the astrocyte cells of rat have been studied. Evaluation was made of the damage to the chromatin of those cells by means of cytochemical (haematoxylin-eosin) analysis and of the state of fragmentation of the DNA by means of the TUNEL technique as well as the protective effect of the peroxide scavenger, troxol, on those events.

Acute Disease↗
PubMed1999

Determination of dopamine D1 receptors in the human uveo scleral tissue by light microscope autoradiography.

The aim of this paper is to clarify the distribution of Dopamine D1 (DA D1) receptors in the uveo-scleral tissue of human eyes with or without elevated intraocular pressure (IOP) and to study the relationships between DA D1 receptors and uveo-scleral tissue. Samples of human uveo-scleral tissue were taken from seven men undergoing eye surgery for a traumatic lesion of the anterior segment of the eye, without involvement of the iris-corneal angle and /or from eye donors. The subjects (in whom one eye bulb had been surgically enucleated) had been previously enrolled in our medical protocols because they suffered for increased IOP, while the eye donors (of both eye bulbs) had a normal IOP. Frozen sections from the uveo-scleral tissue were submitted to biochemical characterization and to morphological autoradiographic techniques for detection of DA-D1 receptors. [3H]-SCH-23390 was used as a ligand of Dopamine D1 receptors. [3H]-SCH 23390 was bound by sections of the human uveo-scleral tissue. The pharmacological profile of the binding was consistent with the labeling of D1 receptors. Light microscope analysis was used for localization of D1 receptors and revealed an accumulation of the radioligand in the human uveo-scleral tissue. In eyes with normal IOP there is a high reaction. The Bmax of radioligand decreases in the eyes with increased IOP. The possibility that dopaminergic receptors play a role in the controlling uveo-scleral tissue functions is suggested.

Adult↗
PubMed1999

Localization of dopamine receptors in the rabbit cornea.

PURPOSE: To analyze the pharmacologic profile and the anatomic localization of the dopamine D1 and D2 receptors in sections of the rabbit cornea in normal conditions. METHODS: Samples of rabbit cornea were drawn. Biochemical and autoradiographic techniques were used on frozen sections. [3H]SCH-23390 was used as a ligand of dopamine D1 receptors and [3H]spiroperidol as a ligand of dopamine D2 receptors. RESULTS: [3H]SCH-23390 and [3H]spiroperidol were bound by sections of the rabbit cornea. The pharmacologic profile of the binding was consistent with the labeling of D1 and D2 receptors, respectively. Light microscopic analysis of the localization of D1 and D2 receptors revealed an accumulation of the two radioligands in the epithelial and in the endothelial layers of the cornea. CONCLUSION: A possible role of the dopaminergic system in the control of the corneal functions is suggested.

Animals↗
PubMed1998

Occurrence of cholinergic nerve fibers in the human uveoscleral tissue.

We have studied the cholinergic nerve fibers (CNF) of human uveoscleral tissue in normal and pathological conditions (intraocular pressure: (IOP) of various degrees ) and have performed a quantitative image analysis of CNF with the aim of studying an hypothetical association between IOP and the uveoscleral level of cholinergic neurotransmitter in nerve fiber of the enucleated human eyes. Eleven patients, previously enrolled in our medical protocols are affected by an increase of IOP of various degrees, were subjected to surgical enucleation of one eyeball for traumatic or neoplastic reasons and were the donors of samples of the uveoscleral tissue for CNF demonstration. The samples were also submitted to quantitative image analysis. An enzymatic activity, Acetylcholinesterase (AChe), is present in nerve fibers that innervate the human uveoscleral tissue. The AChe-positive nerve fibers represent about 7.2% of the observed area in normal conditions, while in patients with elevated IOP AChe activity is about 20.3% of the total observed area. The increase of AChe activity in our experiments, all performed under the same conditions, and therefore, with comparable results, may be related with the increase of IOP.

Acetylcholinesterase↗
PubMed1998

Ultrasound biomicroscopy in the clinical evaluation of ab externo holmium:YAG laser sclerostomies.

High-frequency ultrasound biomicroscopy (UBM) has extensive powers of resolution. This makes it possible to explore and study some areas of the anterior segment with a clarity close to that of histologic preparations. High-frequency UBM was used in the clinical evaluation of 10 glaucomatous eyes subjected to ab externo holmium:yttrium-aluminum-garnet (Ho:YAG) laser sclerostomy. The anatomic characteristics of the fistular paths were viewed and compared with echographic images. The authors demonstrated that in the 5 cases where the filtering bleb, fistular path, and internal ostium were present, there was a reduction of intraocular pressure. UBM is a high-definition diagnostic instrument in the follow-up of fistular paths and filtering blebs after Ho:YAG laser sclerostomy, making it possible to reoperate at an early stage before the onset of clinical manifestations.

Adult↗
PubMed1998

Catecholaminergic nerve fibres in normal and alkali-burned rabbit cornea.

BACKGROUND: In recent years anatomic research has demonstrated the presence of various types of nerve fibre in the cornea. The purpose of this study was to investigate the distribution of catecholaminergic fibres in various corneal layers and to study the effects of an experimental superficial corneal lesion on the pattern of catecholaminergic nerve fibre distribution in the various corneal layers. METHODS: Three weeks after the creation of an alkali burn in the centre of the right cornea of five albino rabbits, the animals were killed, and histologic sections from the cornea of both eyes were stained for observation of catecholaminergic nerve fibres and photographed on black-and-white film. The photographs were examined using the Quantimet image analyser (Leica). RESULTS: Catecholaminergic nerve fibres were observed in the corneal epithelium and the deep stromal layers. Sections from injured cornea showed a drastic reduction in epithelial and superficial stromal catecholaminergic nerve fibres, whereas the nerve fibres in the endothelium and deep stroma were not damaged. INTERPRETATION: Although catecholaminergic nerve fibres were observed in all corneal layers, the pattern of catecholaminergic fibres following the creation of a superficial lesion of the cornea seems to suggest that the superficial and deep nerve fibres may have a different distribution.

Animals↗
PubMed1997

Argon laser photocoagulation in the treatment of the palpebral lobe cysts of the lacrimal gland (dacryops).

Dacryops is a closed cyst that develops on the palpebral lobe of the lacrimal gland, manifesting in the region of the external canthus. Its slow and insidious growth causes mechanical and aesthetic problems that do not regress spontaneously. Treatment involves excision of the cyst while sparing the adjacent glandular tissues. In cases associated with hypolacrimation, marsupialization of the cyst is indicated. To obtain a reduction of the cyst to an aesthetically acceptable level in cases of simple dacryops, the authors suggest argon laser therapy, which avoids the risks related to surgery and general anesthesia and eliminates the need for hospitalization. Two patients with simple dacryops were treated with blue-green argon laser under local anesthesia. At the end of follow-up, the cysts had been clinically reduced in volume and were not visible by external examination. In cases of simple dacryops, laser therapy is suitable for the reduction of the cyst. Photocoagulation treatment is not advisable in cases that are complicated by fistulas or where the clinical presentation is atypical.

Aged↗
PubMed1977

[On the possibility of reducing systemic side-effects of isoproterenol eyedrops by means of topical propranolol (author's transl)].

Topical administration of Isoproterenol reduces the intraocular pressure in glaucomatous eyes, but produces systemic side-effects (tachycardia arterial hypotension) that make its clinical use unadvisable. Such side-effects are significant when the concentration of Isoproterenol is 4 and 5%. Pre-treatment of the contralateral eye with a solution of Propranolol 1%, 30 and 60 min. before Isoproterenol instillation, markedly reduces systemic side-effects, without diminishing the ocular hypotensive effectiveness.

Adolescent↗
PubMed1977

[Topical oxpernolol in the treatment of various forms of glaucoma (author's transl)].

Oxprenolol is a new beta-adrenergic blocking drug, whose effectiveness in the treatment of various forms of glaucoma has been evaluated. The drug was administered topically as 0.5% -1%-2% solution. The results of the investigation may be summarized as follows: The instillation of the drug produces a transient and slight conjunctival hyperaemia and a not significant miosis. A significnat ocular hypotensive action has been observed in the treatment of chronic open-angle, hemorrhagic and congenital glaumiosis. A significnat ocular hypotensive action has been observed in the treatment of chronic open-angle, hemorrhagic and congenital glaucoma. The concentration of 0.5% Oxprenolol seems to be as effective as topical 1% Propranolol. At the same concentration (0.5%), Oxprenolol produces no significnat change of the systemic blood pressure or of the heart rate. Topical pre-treatment with 1% Oxprenolol inhibits the systemic side-effects (tachycardia) produced by topical Isoproterenol, a wellknown ocular hypotensive drug. The authors conclude the investigation affirming that Oxprenolol may represent a new effective means for the medical treatment of glaucoma.

Chronic Disease↗