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Biomedical subjects

G Di Felice

Publications and source records attributed to G Di Felice.

14 recordsLinked to original sources
PubMed1992

Role of carbohydrate moieties in cross-reactivity between different components of Parietaria judaica pollen extract.

Cross-reactivity between the different components in Parietaria judaica pollen extract has been investigated by polyclonal as well as monoclonal antibodies before and after chemical deglycosylation obtained by trifluoromethanesulphonic acid (TFMS) treatment of the extract. In western blotting a polyclonal rabbit antiserum, obtained by injecting purified Par j I, was able to recognise many components of the native extract. However, its reactivity was restricted, after chemical deglycosylation of the extract, to the major allergen alone, indicating that its cross-reactivity was due to sugar moieties. Moreover, out of several monoclonal antibodies raised by injecting the whole Parietaria judaica extract, one (1A4/2F8) was also able in western blotting to recognise an epitope shared by many components of the extract except the major allergen Par j I. However, in this case the broad reactivity of the antibody was not affected by the deglycosylating procedure. When the reactivity of Parietaria judaica extract was tested before and after sugar removal, against specific IgE from a pool of patient sera, no differences could be demonstrated, thus indicating that carbohydrates are not strongly involved in the binding of Parietaria judaica-specific IgE. The results indicate that both proteic and carbohydratic cross-reactive epitopes are shared by many components of Parietaria judaica pollen extract.

Allergens↗
PubMed1991

The current role of endoscopy in Mallory-Weiss syndrome.

We have carried out a retrospective review of 61 patients with Mallory-Weiss syndrome, 9 of whom underwent hemostatic injection treatment. At emergency endoscopy, 3 patients (5%) were actively bleeding and 6 (10%) had stigmata of recent hemorrhage. Fifty-two patients had a lesion of the cardia which was the suspected source of bleeding in 33 cases (54%). In the remaining 19 cases (31%) this site was not considered responsible because other sites of bleeding were present in the upper gastrointestinal tract. The 9 patients with active bleeding or stigmata of recent hemorrhage underwent injection treatment and the other 52 patients were treated with H2 antagonists. The low rebleed rate and the zero mortality recorded in this series indicate that endoscopy is the optimum method for diagnosis and treatment of patients with Mallory-Weiss syndrome.

Adult↗
PubMed1991

Laparoscopic repair of full-thickness stomach injury.

A case of laparoscopic repair of gastric perforation caused by a trocar is reported. Suturing was carried out by the apposition of clips. The potential advantages of this approach are that the treatment is performed at the time of the complication, the duration of the operation is reduced, and the discharge of the patient from hospital is accelerated.

Female↗
PubMed1991

Changes in skin reactivity, specific IgE and IgG levels after one year of immunotherapy in olive pollinosis.

Changes in specific skin reactivity, specific IgE and specific IgG after immunotherapy (IT) were investigated in olive pollinosis. Thirty patients, receiving IT with commercial extracts, were studied in comparison with a control group of seven patients, receiving only drug therapy. Skin reactivity, IgE and IgG were assessed before starting IT and 1 year later. Definite changes in the three considered parameters occurred in patients given IT with Olea europaea extracts; no variation was observed in the control group. The specific skin reactivity, evaluated by means of quantitative skin prick tests, significantly decreased (Skin Index geometrical mean from 2.73 to 0.88, P less than 0.001); the specific IgE, measured by RAST, were surprisingly decreased (from 7.76 to 4.74 PRU/ml, P less than 0.001); the specific IgG, measured by ELISA, in basic conditions were detectable only in nine patients of 30, while, after IT, they were found in almost all patients with a remarkable increase (from 5.48 to 266.89 AU/ml, P less than 0.001). No correlation was found among the changes in the considered parameters, suggesting that, at least in olive pollinosis, specific skin reactivity, specific IgE and specific IgG are three variables depending on IT but reciprocally independent.

Adult↗
PubMed1991

Use of monoclonal antibodies for the characterization of allergenic extracts.

The diagnosis of allergic diseases is commonly carried out by using poorly standardized preparations containing allergenic and non-allergenic components. Recently, monoclonal antibody technology has been applied to the biochemical characterization and to the purification of allergens, in order to evaluate their potential role in the standardization of diagnostic and therapeutic extracts. Three main results have been achieved: 1) the characterization of allergenic epitopes recognized by IgE and IgG from patients' sera; 2) the purification by affinity chromatography of relevant allergenic components; 3) the development of immunoassays for the quantitation of allergens in the commercially available extracts used for diagnosis and therapy.

Allergens↗
PubMed1991

Allergens and atopic diseases.

Allergens are molecules normally present in the environment, responsible of inducing the so called atopic diseases. These diseases are characterized by the high production of allergen-specific IgE antibodies, which bind to mast-cells and basophils. The cross-linking of the cell-bound IgE induces the production and/or release of various inflammatory mediators (histamine, leukotrienes, platelet-activating-factor, etc.), which trigger a cascade of events resulting in the allergic syndromes. Once the diagnosis of allergy has been made, two different therapeutic approaches can be followed: a) the pharmacologic management, aimed mainly at preventing or controlling the symptoms resulting from the release of mediators by effector cells; b) the specific immunotherapy, consisting in the administration to the patient of increasing amount of the relevant allergens, opportunely prepared and eventually chemically modified. In order to have the latter approach correctly applied it is necessary to gain a wider knowledge on both regulation of IgE synthesis and allergens characteristics.

Allergens↗
PubMed1990

Small-cell carcinoma of the esophagus. Treatment by endoscopy.

A case of primary carcinoma of the esophagus is presented that consisted of poorly differentiated small-cell carcinoma. The patient underwent endoscopic treatment, first with an Nd:YAG laser and, finally, with bougienage and the insertion of a prosthesis in order to relieve dysphagia and improve the nutritional status and quality of life. Even though it is generally uncommon for laser therapy to be chosen as a primary mode of treatment, the results obtained should permit to overcome this lack of confidence in the choice of laser treatment for small-cell carcinoma of the esophagus.

Aged↗
PubMed1989

T cell responses to a Parietaria judaica pollen extract: comparison between Parietaria-sensitive patients, other atopics and healthy controls.

We investigated the in vitro proliferation of peripheral blood mononuclear cells (PBMC) from Parietaria-allergic subjects, atopic patients with other sensitizations and healthy controls to Parietaria judaica pollen extracts. PBMC from almost all 44 subjects, divided into five groups (Parietaria-, grass-, Parietaria and grass-, Dermatophagoides-sensitive patients and normal individuals) were able to proliferate in response to the extract without statistically significant differences between groups. Mean values of the stimulation indexes for the five groups were respectively: 10.73, 3.18, 5.50, 10,56, 9.28. The results of separation experiments showed that the responding cells were T lymphocytes. Mitogenic effect of the Parietaria pollen extract was excluded by the absence of proliferative PBMC response from cord blood of seven newborns. These results indicate that Parietaria-sensitive, other atopics and normal individuals have Parietaria-specific T cells able to proliferate in vitro to Parietaria allergens.

Cell Separation↗
PubMed1987

Endoscopic injection treatment in patients with shock and gastrointestinal bleeding or stigmata of recent hemorrhage.

Forty cases of upper gastrointestinal bleeding were studied. Twenty-three patients had shock and active bleeding (3 spurting, 12 oozing and 2 a clot with oozing) or stigmata of recent hemorrhage (4 with a clot and 2 with a visible vessel). Nineteen of these were submitted to endoscopic injection. In 4 cases with multiple acute hemorrhagic lesions and shock, and in 17 patients with stigmata of recent bleeding without shock, the technique was not carried out. None of the patients had a rebleed. One patient was submitted to surgery 24 hours after injection for a large acute gastric ulcer in the process of perforating, and died of pulmonary embolism 4 days later. No technique-related complications were observed. We believe endoscopic injection treatment might be the technique of choice in patients with shock and active bleeding or stigmata of recent hemorrhage of the upper gastrointestinal tract.

Adult↗
PubMed1986

Purification and partial characterization of the major antigen of Echinococcus granulosus (antigen 5) with monoclonal antibodies.

A monoclonal antibody specific for antigen 5 of Echinococcus granulosus was isolated and partially characterized. Purification of antigen 5 was accomplished by affinity chromatography using an immunoabsorbent prepared with this monoclonal antibody. Pure antigen 5 was identified by immunoelectrophoresis, double diffusion in agar gel, sodium dodecyl sulphate-polyacrylamide gel electrophoresis and immunoblotting. The pure antigen displayed the electrophoretic mobility typical of antigen 5 and gave a single precipitin band in double diffusion with both monoclonal antibody and rabbit anti-pH5PPT hydatid fraction serum. Two bands of 66 and 56 kDa could be detected in the pure antigen 5 after sodium dodecyl sulphate-polyacrylamide gel electrophoresis when performed in non-reducing conditions: both bands were reactive with the monoclonal antibody in immunoblotting. After reduction with 2-mercaptoethanol, antigen 5 displayed one band only, of 39 kDa. Antigen 5 purified by this procedure was found to retain reactivity with human sera from hydatid patients in a DD5 test.

Animals↗