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Biomedical subjects

G Ferrara

Publications and source records attributed to G Ferrara.

At least 19 recordsLinked to original sources
PubMed2006

CFD analysis of gas explosions vented through relief pipes.

Vent devices for gas and dust explosions are often ducted to safe locations by means of relief pipes. However, the presence of the duct increases the severity of explosion if compared to simply vented vessels (i.e. compared to cases where no duct is present). Besides, the identification of the key phenomena controlling the violence of explosion has not yet been gained. Multidimensional models coupling, mass, momentum and energy conservation equations can be valuable tools for the analysis of such complex explosion phenomena. In this work, gas explosions vented through ducts have been modelled by a two-dimensional (2D) axi-symmetric computational fluid dynamic (CFD) model based on the unsteady Reynolds Averaged Navier Stokes (RANS) approach in which the laminar, flamelet and distributed combustion models have been implemented. Numerical test have been carried out by varying ignition position, duct diameter and length. Results have evidenced that the severity of ducted explosions is mainly driven by the vigorous secondary explosion occurring in the duct (burn-up) rather than by the duct flow resistance or acoustic enhancement. Moreover, it has been found out that the burn-up affects explosion severity due to the reduction of venting rate rather than to the burning rate enhancement through turbulization.

Explosions↗
PubMed2006

Three-point checklist of dermoscopy: an open internet study.

BACKGROUND: In a pilot study, the three-point checklist of dermoscopy has been shown to represent a valid and reproducible tool with high sensitivity for the diagnosis of skin cancer in the hands of a small group of nonexperts. OBJECTIVES: To re-evaluate these preliminary results in a large number of observers independently from their profession and expertise in dermoscopy. METHODS: The study was conducted via the internet to provide worldwide access for participants. After a short web-based tutorial, the participants evaluated dermoscopic images of 165 (116 benign and 49 malignant) skin lesions (15 training and 150 test lesions). For each lesion participants scored the presence of the three-point checklist criteria (asymmetry, atypical network and blue-white structures). Kappa values, odds ratios, sensitivity, specificity and likelihood ratios were estimated. RESULTS: Overall, 150 participants joined the study. The three-point checklist showed good interobserver reproducibility (kappa value: 0.53). Sensitivity for skin cancer (melanoma and basal cell carcinoma) was 91.0% and this value remained basically uninfluenced by the observers' professional profile. Only 20 participants lacking any experience in dermoscopy performed significantly more poorly, but the sensitivity was still remarkably high (86.7%) when considering that they were untrained novices in dermoscopy. The specificity was 71.9% and was significantly influenced by the profession, with dermatologists performing best. CONCLUSIONS: Our study confirms that the three-point checklist is a feasible, simple, accurate and reproducible skin cancer screening tool.

Basal Cell Carcinoma↗
PubMed2006

Glomangioma in the prepuce of a dog.

A case of preputial glomangioma in an 8-year-old Springer Spaniel dog is reported. The dog presented a solitary nodular mass, approximately 3.5 x 5.2 cm in diameter, located on the lateral wall of the prepuce at the base of the penis. Histologically, the excised tumour mass consisted of proliferating round epithelioid cells arranged in a cordon-like structure around small blood vessels. The neoplastic cells were positive for alpha smooth muscle actin and negative for cytokeratin, desmin, S-100 protein and neurone-specific enolase. Based on these pathologic features, the tumour was diagnosed as glomangioma, a neoplasm extremely rare in dogs. To our knowledge, this is the first report of preputial glomangioma in the dog.

Animals↗
PubMed2005

Humic acids reduce the genotoxicity of mitomycin C in the human lymphoblastoid cell line TK6.

The antimutagenic/desmutagenic activity of a leonardite humic acid (LHA) and a soil humic acid (SHA) was studied in the cultured human lymphoblastoid cell line TK6 treated with mitomycin C (MMC) as reference mutagen by evaluating the induction of micronuclei (MN). Two different concentrations of HA were used, 2.5 and 10 microg/ml, in three different treatments: (1) HA alone (genotoxic test); (2) HA after 2-h pre-incubation with 0.3 microM of MMC (desmutagenic test) and (3) combinations of HA and MMC at 0.3 microM without pre-incubation (antimutagenic test). Neither of the HA used alone did produce genotoxic effects, but both HAs reduced significantly the frequencies of MN induced by MMC, especially in the desmutagenic test. A slight cell-protective effect against the cytotoxicity of MMC was also exhibited by the two HAs in the desmutagenic test. The LHA showed a desmutagenic/antimutagenic activity that was more pronounced than that of SHA, which is possibly related to the higher carboxylic group content and lower phenolic group content of LHA. These results confirm the antigenotoxic action exerted by HAs in human cells, similarly to what has been previously observed in various plant species.

Antibiotics, Antineoplastic↗
PubMed2005

Macrolides for chronic asthma.

BACKGROUND: Asthma is a chronic disease of the airways in which inflammation of the respiratory mucosa plays a crucial role. The mechanisms responsible for the maintaining of this inflammatory response are only partially known and there is evidence that a role could be paid by chronic infection by intracellular pathogens (such as Chlamydia pneumoniae). Macrolides are antibiotics with both antimicrobic and antiinflammatory activities and thus their use in asthmatic patients could lead to reduction of the airways inflammation and therefore improvement of symptoms and pulmonary function. OBJECTIVES: To determine whether macrolides are effective in the management of patients with chronic asthma. SEARCH STRATEGY: We searched the Cochrane Airways Group Specialised Register of trials up to May 2005. This was also supplemented by manually searching bibliographies of previously published reviews, conference proceedings, and contacting study authors. All languages were included in the initial search. SELECTION CRITERIA: Randomised, controlled clinical trials involving both children and adult patients with chronic asthma treated with macrolides for more than 4 weeks, versus placebo. DATA COLLECTION AND ANALYSIS: Two reviewers independently examined all identified articles. The full text of any potentially relevant article was reviewed independently by two reviewers. MAIN RESULTS: Seven studies recruiting a total of 416 participants met the inclusion criteria. The quality of reporting of study methodology was generally low. We assembled findings from studies comparing macrolide treatment for at least 4 weeks in adult and pediatric patients treated for chronic asthma. Four studies showed a positive effect on symptoms of macrolides in different types of asthmatic patients. There were limited data available for meta-analysis. There was no significant difference in FEV1 for either parallel or crossover trials. However, there were significant differences in eosinophilic inflammation and symptoms. One large parallel group trial reported significant differences in peak flow but these differences abated within six months of treatment. AUTHORS' CONCLUSIONS: Considering the small number of patients studied, there is insufficient evidence to support or to refute the use of macrolides in patients with chronic asthma. Further studies are needed in particular to clarify the potential role of macrolides in some subgroups of asthmatics such as those with evidence of chronic bacterial infection.

Anti-Bacterial Agents↗
PubMed2005

Macrolides for chronic asthma.

BACKGROUND: Asthma is a chronic disease of the airways in which inflammation of the respiratory mucosa plays a crucial role. The mechanisms responsible for the maintaining of this inflammatory response are only partially known and there is evidence that a role could be paid by chronic infection by intracellular pathogens (such as Chlamydia pneumoniae). Macrolides are antibiotics with both antimicrobic and antiinflammatory activities and thus their use in asthmatic patients could lead to reduction of the airways inflammation and therefore improvement of symptoms and pulmonary function. OBJECTIVES: To determine whether macrolides are effective in the management of patients with chronic asthma. SEARCH STRATEGY: We searched the Cochrane Airways Group Specialised Register of trials up to May 2004. This was also supplemented by manually searching bibliographies of previously published reviews, conference proceedings, and contacting study authors. All languages were included in the initial search. SELECTION CRITERIA: Randomised, controlled clinical trials involving both children and adult patients with chronic asthma treated with macrolides for more than 4 weeks, versus placebo. DATA COLLECTION AND ANALYSIS: Two reviewers independently examined all identified articles. The full text of any potentially relevant article was reviewed independently by two reviewers. MAIN RESULTS: Seven studies recruiting a total of 416 participants met the inclusion criteria. The quality of reporting of study methodology was generally low. We assembled findings from studies comparing macrolide treatment for at least 4 weeks in adult and pediatric patients treated for chronic asthma. Four studies showed a positive effect on symptoms of macrolides in different types of asthmatic patients. There were limited data available for meta-analysis. There was no significant difference in FEV1 for either parallel or crossover trials. However, there were significant differences in eosinophilic inflammation and symptoms. One large parallel group trial reported significant differences in peak flow but these differences abated within six months of treatment. AUTHORS' CONCLUSIONS: Considering the small number of patients studied, there is insufficient evidence to support or to refute the use of macrolides in patients with chronic asthma. Further studies are needed in particular to clarify the potential role of macrolides in some subgroups of asthmatics such as those with evidence of chronic bacterial infection.

Anti-Bacterial Agents↗
PubMed2005

Macrolides in the treatment of asthma and cystic fibrosis.

Asthma and cystic fibrosis are two respiratory diseases characterized by chronic inflammation, leading to remodelling of the airways. Macrolides are widely used antibiotics, with a peculiar anti-inflammatory effect. On the basis of the methodologies used by the Cochrane collaboration, this review discusses the evidence for their long-term use as anti-inflammatory agents in these two diseases. Three randomized-controlled trials (RCTs) were identified for both asthma and cystic fibrosis. A positive effect of macrolides on reducing eosinophil numbers and markers of eosinophilic inflammation was demonstrated in patients with asthma. Data on cystic fibrosis demonstrated an effect on lung function with an increase of 5.4% in forced vital capacity (FVC) in patients treated with macrolide vs. placebo, but without a significant effect on FEV1. Side-effects were rare, mild and reversible on withdrawal of treatment. Although preliminary data from small studies are promising, the role of macrolides in the treatment of these chronic disorders needs to be more firmly established with larger, well-designed trials, targeted to investigate major clinical outcomes.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2005

Dermoscopy for challenging melanoma; how to raise the 'red flag' when melanoma clinically looks benign.

Melanoma may mimic clinically a number of benign skin tumours by exhibiting overlapping features that do not allow accurate differentiation. Dermoscopy is a noninvasive diagnostic tool allowing the evaluation of specific subsurface morphological structures that are useful in most cases to distinguish melanoma from other melanocytic and nonmelanocytic skin tumours. In order to minimize the risk of missing melanoma, the diagnosis should be based on a good correspondence between the clinical and the dermoscopic findings. The case presented here refers to a melanoma clinically simulating dermatofibroma that was biopsied because dermoscopic examination revealed unusual features that did not confirm the clinical diagnosis.

Adult↗
PubMed2005

Management of multidrug-resistant tuberculosis in Italy.

SETTING: SMIRA (Italian Study on Anti-Tuberculosis Drug Resistance) network, 46 major clinical units and 22 laboratories nationwide in Italy. OBJECTIVES: To determine the main features, adherence to WHO guidelines and the outcomes of multidrug-resistant tuberculosis (MDR-TB) patients enrolled from January 1995 to December 1999. DESIGN: Observational study, preceded by proficiency testing, according to WHO recommendations. Results were stratified by appropriate and inappropriate regimens (< three active drugs). Analysis of the outcomes was performed according to adequacy of treatment. Analysis of risk factors and factors predicting treatment outcomes was performed using univariate and multivariate analysis (level of significance P < 0.05). RESULTS: One hundred and twenty-seven MDR patients were diagnosed. The overall success rate was low (39%). Seventy per cent of cases were treated with at least three active drugs. Factors predicting treatment success were new MDR-TB cases (OR 3.45; 95% CI 1.22-9.78; P < 0.05) and treatment for > or = 12 months (OR 5.03; 95% CI 1.65-15. 31; P < 0.05). Immigration and HIV infection were the main risk factors among new MDR-TB cases. CONCLUSION: The best available treatment should be provided to all newly diagnosed MDR-TB patients, avoiding the use of poorly modified regimens. MDR-TB patients should be referred to highly specialised centres.

Adult↗
PubMed2004

Benign fibrous histiocytoma of prepuce in the mule.

Here we present a case of preputial benign fibrous histiocytoma in a 7-year-old mule. This case was treated surgically. Pathologic analysis and diagnosis of these lesions were based on a combination of light microscopy and immunohistochemistry. Histologically, the tumour was composed primarily of a storiform pattern of fibroblastic and poligonal cells. In immunohistochemistry, except for consistent immunoreactivity for vimentin, nearly all tumour cells were positive for CD68, S-100 protein, pan-cytokeratin, alpha-smooth muscle actin, and desmin. Benign fibrous histiocytoma of the prepuce in mule is rarely reported in veterinary literature.

Animals↗
PubMed2004

Clinically equivocal melanocytic skin lesions with features of regression: a dermoscopic-pathological study.

BACKGROUND: Benign melanocytic skin lesions may be difficult to differentiate from melanoma both clinically and dermoscopically. One of the most confounding dermoscopic features, commonly seen in melanoma but in our experience also in melanocytic naevi, is represented by the so-called blue-white structures (BWS). OBJECTIVES: To evaluate diagnostic significance and histopathological correlates of BWS seen by dermoscopy in a series of clinically equivocal melanocytic skin lesions that were excised. METHODS: Patients were recruited from six specialized pigmented lesion clinics in Austria, Italy and Spain over a period of 9 months. All consecutive patients showing one or more melanocytic lesions with BWS, but not classified as melanoma dermoscopically, were included. Each lesion was photographed clinically and dermoscopically. All images were reviewed by one of us and the degree, type and location of BWS evaluated for each lesion. A panel of four experienced dermatopathologists independently reviewed all specimens for diagnosis and one of them evaluated presence and degree of melanosis and/or fibrosis. The main outcome measures were the percentage and histopathological correlates of lesions with different degree, type and location of BWS. RESULTS: All included lesions with BWS (n = 158) showed partial or focal regression histopathologically. One hundred and thirty-five (85.4%) lesions were diagnosed as melanocytic naevi (complete histopathological interobserver agreement), whereas 23 (14.6%) were defined as equivocal because at least one of four pathologists diagnosed the given lesion as melanoma. Only one lesion was diagnosed as melanoma by all four pathologists. The majority of naevi exhibited blue areas (84.4%) with a central distribution (57%) and involving < 50% of the lesion surface (89.6%). By contrast, 78.3% of equivocal lesions revealed a combination of white and blue areas with an irregular distribution (60.9%) and involving > 50% of the lesion surface (47.8%). CONCLUSIONS: Using degree and type of BWS, an algorithm was constructed that can be applied for the management of lesions exhibiting dermoscopic features of regression.

Adolescent↗
PubMed2003

Corticosteroids for idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF), also called cryptogenic fibrosing alveolitis (CFA), is a lethal form of diffuse lung disorder of unknown origin; the mean survival being two to four years. Currently recommended and most prescribed therapy for IPF is based on the use of systemic corticosteroids, even if no formal demonstration of efficacy of this treatment of IPF is available. Furthermore, new insights from pathological studies have produced a new hypothesis, based upon the central role played by aberrant wound healing following repeated lung injury, weakening the rationale basis of the use of corticosteroids in IPF, previously considered simply a chronic inflammatory disease. OBJECTIVES: The objective of the review was to determine the efficacy of corticosteroids in the treatment of adults with IPF. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2002), MEDLINE (January 1966 to May 2002) and EMBASE (January 1985 to December 2002) and reference lists of articles. We searched reference lists of published articles to identify trials. SELECTION CRITERIA: Randomised controlled trials (RCT) and controlled clinical trials (CCT) using corticosteroids alone for the treatment of adults with IPF. DATA COLLECTION AND ANALYSIS: Abstracts of identified articles were retrieved and articles possibly fulfilling inclusion criteria were retrieved in full. Two reviewers would have independently assessed trial quality if there had been any included studies. MAIN RESULTS: Fifteen studies were selected as potentially eligible for meta-analysis. After further analysis of full text papers, no RCTs or CCTs were identified as suitable and therefore no data was available for inclusion in any meta-analysis. All studies were excluded due to inadequate methodologies. REVIEWER'S CONCLUSIONS: At present, there is no evidence for an effect of corticosteroid treatment in patients with Idiopathic pulmonary fibrosis(IPF)/usual interstitial pneumonia (UIP). Given developments in understanding of the pathogenesis of IPF, randomised controlled trials designed to test the efficacy of corticosteroids will probably never be designed. As other forms of pulmonary fibrosis such as non-specific interstitial pneumonia are reported to show a better response to corticosteroids, it is crucial to make an accurate diagnosis in each patient. Moreover, therapies with immunomodulatory rather than anti-inflammatory or immunosuppressive effects may be more promising for the effective treatment of IPF/UIP.

Adrenal Cortex Hormones↗
PubMed2003

Reinke's crystals in an interstitial cell tumour of a rabbit (Oryctolagus cuniculus).

One case of interstitial cell tumour in the testicle of a New Zealand White rabbit was reported. The rabbit was 9-years old and had monolateral testicular lesion. There was enlargement of left testis and the lesion were seen on the cut surface. Light microscopy revealed intracytoplasmic crystals of Reinke that resembled to the features observed for this tumour in human. Immunohistochemically, this tumour was positive for vimentin.

Animals↗