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Stefano Bonini

Publications and source records attributed to Stefano Bonini.

28 records · Page 2Linked to original sources
PubMed2003

Topical treatment of pressure ulcers with nerve growth factor: a randomized clinical trial.

BACKGROUND: The prevalence of pressure ulcers of the foot is a major health care problem in frail elderly patients. A pressure sore dramatically increases the cost of medical and nursing care, and effective treatment has always been an essential nursing concern. Management options for pressure ulcers include local wound care; surgical repair; and, more recently, topical application of growth factors. OBJECTIVE: To examine the effects of topical treatment with nerve growth factor in patients with severe, noninfected pressure ulcers of the foot. DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING: Teaching nursing home of Catholic University of the Sacred Heart, Italy. PATIENTS: 36 persons with pressure ulcers of the foot. INTERVENTION: 18 patients received nerve growth factor treatment, and 18 patients received only conventional topical treatment. MEASUREMENTS: The course of the ulcers during follow-up was evaluated by tracing the perimeter of the wound onto sterile, transparent block paper and determining the stage. RESULTS: At baseline, the treatment and control groups did not differ across demographic variables, clinical characteristics, and functional measures. The mean area (+/-SD) of the ulcers was 1012 +/- 633 mm2 in the treatment group and 1012 +/- 655 mm2 in the control group (P > 0.2). The average reduction in pressure ulcer area at 6 weeks was statistically significantly greater in the treatment group than in the control group (738 +/- 393 mm2 vs. 485 +/- 384 mm2; P = 0.034). CONCLUSION: Topical application of nerve growth factor may be an effective therapy for patients with severe pressure ulcers.

Administration, Topical↗
PubMed2003

Nerve growth factor (NGF) and lenses: effects of NGF in an in vitro rat model of cataract.

BACKGROUND: The aims of this study are to investigate the presence and production of nerve growth factor (NGF) in the rat lens in basal conditions and to evaluate, in vitro, the role of NGF in a model of xylose-induced cataract. METHODS: Rat lenses were dissected and the expression of NGF, NGF mRNA and high-affinity NGF-receptor (TrkA) was evaluated by immunohistochemistry, immunoenzymatic assay (ELISA) and in-situ hybridization (ISH) techniques. To investigate the role of NGF in cataract formation we used an in vitro model of sugar-induced cataract by culturing rat lenses for 48 h in Eagle's minimum essential medium (MEM) supplemented with xylose. To evaluate the potential protective effect of NGF on xylose-induced cataract formation, exogenous NGF at different concentrations or antibodies neutralizing endogenous NGF (NGF-Ab) or aspecific antibodies were added to xylose-cultured lenses, and the following cataract-related parameters were evaluated and compared to xylose-treated lenses. Cataract formation was evaluated using three different parameters: staging of the cataract by lens photography, quantification of lens transparency in terms of gray level medium (GLM) and evaluation of the hydration percentage (H%) of the lens. To investigate the role of endogenous NGF in cataract onset, NGF levels were evaluated and compared in lenses cultured in xylose supplemented medium versus lenses cultured in control culture medium. RESULTS: The epithelium from fresh rat lenses expresses NGF-receptor, NGF protein and NGF-mRNA. NGF levels in fresh lens were 54.0 +/- 24.5 pg/g as quantified by ELISA. Xylose-cultured lenses develop cataract changes, including a decrease of GLM and an increase in hydration percentage, associated with a decrease in NGF levels when compared to lenses cultured in the control culture medium. The addition of NGF to xylose-cultured lenses reduces cataract formation, increasing GLM and decreasing the hydration percentage as compared to xylose-treated lenses. On the other hand, the addition of NGF-Ab induces an increase in cataract formation and lens hydration. CONCLUSIONS: This study demonstrates that rat lens epithelium expresses and synthesizes NGF. Moreover, immunohistochemistry shows that lens epithelial cells also express the NGF receptor. Although the functional significance of TrkA on lens epithelium is at present not clear, the expression of NGF and its high-affinity receptor on the same cells together with our experimental results suggest that NGF is involved in supporting trophism and/or the function of the lens epithelium.

Animals↗
PubMed2003

Preservative-free diclofenac sodium 0.1% for vernal keratoconjunctivitis.

PURPOSE: The aim of this study is to evaluate the efficacy of prolonged treatment with preservative-free diclofenac sodium 0.1% eye drops in patients with vernal keratoconjunctivitis (VKC). METHODS: A prospective open study was performed in 22 patients with VKC treated with preservative-free diclofenac sodium 0.1% eye drops. Patients used the eye drops four times daily in both eyes for 120 days. Signs (papillae, hyperaemia and corneal lesions) and symptoms (itching, redness and photophobia) of the ocular surface were graded and statistically evaluated before and after treatment by a non-parametric test (Mann-Whitney U-test). RESULTS: Forty per cent of the patients showed an improvement in their symptoms at the end of the treatment. Total signs and symptoms scores were significantly decreased at the end of treatment compared with the baseline values (from 6.13+/-1.45 to 0.81+/-0.90 and from 5.40+/-1.18 to 2.63+/-0.95, respectively; P<0.001). Significant decreases in conjunctival redness (P<0.001), itching (P<0.001) and photophobia (P<0.001 ) were observed at the end of treatment. Conjunctival hyperaemia was significantly reduced (P<0.001) at the end of treatment, while no significant differences were observed for corneal lesions and for papillary size. No patient showed exacerbation of the disease during the treatment. CONCLUSION: VKC is a chronic disease that requires prolonged treatment to control the inflammatory process. Our preliminary study demonstrates the efficacy and safety of preservative-free diclofenac sodium 0.1% eye drops in controlling the signs and symptoms of VKC in prolonged treatment.

Adolescent↗
PubMed2003

Montelukast, a leukotriene receptor antagonist, in vernal keratoconjunctivitis associated with asthma.

OBJECTIVE: To evaluate the effects on signs and symptoms of a coexisting vernal keratoconjunctivitis in patients treated with oral montelukast sodium for asthma. METHODS: Twelve patients with vernal keratoconjunctivitis and asthma were enrolled in this pilot study. Topical eyedrops or any systemic treatment was discontinued for at least 7 days before montelukast treatment. Patients were asked to grade their ocular discomfort daily. The following signs and symptoms were also recorded and graded through medical examination at baseline,after 15 days of treatment, and 15 days after treatment discontinuation: physician-evaluated tarsal and bulbar papillae, hyperemia, secretion, and chemosis; and patient-evaluated itching, burning, tearing, photophobia, foreign body sensation, secretion, and redness. Peak expiratory flow rate at 8 AM was also recorded. Samples were collected at the same time points for enzyme-linked immunosorbent assay measurement of leukotriene B4 in tears and leukotriene E4 in urine. RESULTS: Eight of the 10 patients evaluated reported a reduction in symptoms at the end of treatment. Montelukast treatment significantly decreased physician-rated hyperemia, secretion, and chemosis as well as patient-rated burning, tearing, photophobia, secretion, and redness. Effects persisted 15 days after discontinuation of treatment. Clinical changes were associated with a significant increase in leukotriene B4 in tears and a significant decrease in leukotriene E4 in urine after 15 days of treatment. CONCLUSION: The significant and persistent reduction of ocular signs and symptoms in asthmatic patients with vernal keratoconjunctivitis treated for 15 days with montelukast strongly suggests the need for double-masked placebo-controlled trials to confirm the potential of this new treatment in vernal keratoconjunctivitis.

Acetates↗
PubMed2003

Allergic chronic inflammation of the ocular surface in vernal keratoconjunctivitis.

PURPOSE OF REVIEW: The purpose of this review is to describe the new immunopathologic features of vernal keratoconjunctivitis: the involvement of cytokines, growth factors, cells, mediators and neurotransmitters, as well as the mechanism leading to tissue remodelling. RECENT FINDINGS: Vernal keratoconjunctivitis is an allergic eye disease affecting young boys living in a warm climate. It is characterized by conjunctival giant papillae, hyperemia and frequent involvement of the cornea. Approximately 50% of the patients with vernal keratoconjunctivitis do not have a family or medical history of atopic diseases, and do not show IgE sensitization, suggesting that this disease is not solely IgE mediated. Vernal keratoconjunctivitis is a Th2 lymphocyte driven disease with a Th2 cytokine derived pattern, increased levels of mRNA for IL-3, IL-4, IL-5 and IL-13. Th2 lymphocytes induce IgE hyperproduction, activation of mast cells, eosinophils, neutrophils and their toxic products. An overexpression of adhesion molecules, RANTES, eotaxin and metalloproteinases contribute to chronic inflammation. A role for substance P and nerve growth factor has been postulated, as well as for other growth factors (epidermal growth factor, fibroblast growth factor and transforming growth factor beta 1) that induce fibroblast growth and new collagen production. Recent studies have also pointed out the role of resident conjunctival cells, such as epithelial cells and fibroblasts, in the inflammatory and remodelling process of vernal keratoconjunctivitis. The pathogenesis of the condition is probably multifactorial, with the interaction of the immune, nervous and endocrine systems. SUMMARY: Vernal keratoconjunctivitis is a chronic inflammatory and potentially blinding disease. Understanding of the complex interactions and cross talk between cells, cytokines and other mediators is relevant for new therapeutic approaches.

Adolescent↗
PubMed2002

Intraocular production and release of nerve growth factor after iridectomy.

PURPOSE: To determine the presence of nerve growth factor (NGF), NGF mRNA, and NGF receptor (TrkA) in rabbit ocular tissues, and whether changes occur in NGF and NGF mRNA levels after experimental iridectomy. METHODS: Immunohistochemistry for NGF and TrkA and in situ hybridization for NGF mRNA were performed on rabbit cornea, iris, ciliary body, and lens in the basal state. Quantification of NGF mRNA and NGF protein levels in these tissues was performed by RT-PCR and immunoenzymatic assay, respectively. A time course of NGF concentration in the aqueous humor and the expression of NGF mRNA in iris and ciliary body were performed after the iridectomy and were compared with levels in a sham-treated group (paracentesis). RESULTS: Cornea, iris, ciliary body, and lens expressed NGF mRNA, NGF protein, and TrkA in the basal state. The highest levels of NGF were detected in the iris (8938.0 +/- 3968.1 pg/g), and the lowest were in the aqueous humor (22.8 +/- 9.7 pg/mL). Experimental iridectomy induced a transient increase of NGF concentration in the aqueous humor that reached its peak 4 hours after the experimental injury (464.4 +/- 29.9 pg/mL versus the control group 101.6 +/- 18.8 pg/mL; P < 0.001) and returned to baseline value after 7 days. A significant increase of NGF mRNA was also observed 1 hour and 4 hours after the iridectomy in the iris (1 hour, 788 +/- 85 OD; 4 hours, 760 +/- 81 OD versus baseline, 246 +/- 32 OD; P < 0.0001) and ciliary body (1 hour, 330 +/- 19 OD; 4 hours, 453 +/- 52 OD versus baseline, 219 +/- 37 OD; P < 0.05), but not in the cornea, lens, or any tissues from the control group. CONCLUSIONS: NGF is present and produced in the anterior segment of the eye and is released in the aqueous humor in the basal state. Experimental iridectomy induces increased production of NGF in the iris and in the ciliary body and an increased concentration of NGF in the aqueous humor.

Animals↗