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P Conti

Publications and source records attributed to P Conti.

At least 181 records · Page 10Linked to original sources
PubMedDate not supplied

MCP-1 and RANTES are mediators of acute and chronic inflammation.

Regulation of leukocyte migration and activation by chemokines are recognized as potentially important functions in the induction of acute and chronic inflammatory reactions. Regulated upon activation normal T cell expressed and presumably secreted (RANTES), monocyte chemotactic protein-1 (MCP-1), and related molecules constitute the C-C class of the beta chemokine supergene family with inflammatory properties. Here we report that in experimental studies RANTES and MCP-1 provoke mast cell activation and increase histidine decarboxylase mRNA expression in a dose-dependent manner. Moreover, injections of RANTES and MCP-1 in the rat skin cause mast cell, eosinophil, and macrophage recruitment, and prostaglandin E2 (PGE2) generation. In a chronic inflammatory model MCP-1 was found to mediate the recruitment of mononuclear cells in calcified granulomas. In addition, MCP-1 mediated parasitic infections caused by Trichinella spiralis. In accordance with other studies, RANTES and MCP-1 were found to play an important role in the lung allergic inflammation, lung leukocyte infiltration, bronchial hyperresponsiveness, and the recruitment of eosinophils in the pathogenesis of asthma. Here for the first time we propose a new mechanism of pulmonary airway inflammation where RANTES and MCP-1 are deeply involved. We also studied the apparent role played by RANTES in the pathogenesis of relapsing-remitting multiple sclerosis enhancing the inflammatory response within the nervous system.

Animals↗
PubMedDate not supplied

Seasonal variability of non-specific bronchial responsiveness in asthmatic patients with allergy to house dust mites.

The aim of the study was to assess the seasonal variability of non-specific bronchial responsiveness to methacholine in allergic asthma. One hundred sixty-five patients (83 male and 82 female) entered the study: 86 subjects (group A) with allergy exclusively to mites and 79 (group B) with concomitant allergy to pollens, e.g., "Graminae" and "Parietaria." Inclusion criteria were the absence of sensitization to other allergens, no smoking habit, withdrawal from steroids, bronchodilators, sodium cromoglycate, and antihistamines for at least four weeks before enrollment, FEV1 > 70% of the predicted value, and absence of other respiratory diseases and of upper and lower respiratory tract infections for at least one month before the methacholine challenge. None of the patients had been previously treated with specific immunotherapy. Subjects of each group (A and B) underwent methacholine challenge at first visit and were divided into four subgroups according to the period when the challenge was performed. Subgroups A1 and B1 performed the challenge in December, January, and February; subgroups A2 and B2 in March, April, and May; subgroups A3 and B3 in June, July, and August; subgroups A4 and B4 in September, October, and November. PD20 values were expressed as the natural logs of the cumulative dose of methacholine causing at least a 20% fall in FEV1. Statistical analysis was carried out using multiple group analysis and Student's t-test. Results showed that the highest non-specific bronchial responsiveness was observed in autumn (ln PC20 = 4.54 +/- 1.51) in patients allergic to mites only (group A), and in summer (ln PC20 = 4.72 +/- 2.11) in those of group B. Multiple group analysis showed statistical significant differences between subgroups within each group (group A, p = 0.039; group B, p < 0.001). In patients allergic exclusively to house dust mites (group A), multiple comparisons and Student's t-test showed statistically significant differences between non-specific bronchial responsiveness (NSBR) assessed in autumn and those of other seasons (winter, p = 0.002; spring, p < 0.001; summer, p = 0.082). These results confirm that the level of allergen exposure may influence NSBR. Mite-allergic patients showed an increase of NSBR in autumn, possibly as a consequence of higher indoor mite concentration. However, mite- and grass-allergic patients had wider variations of NSBR, possibly reflecting changes in seasonal pollen concentration.

Adolescent↗
PubMedDate not supplied

Chemokines in inflammatory states.

Chemokines probably mediate inflammation in asthma by acting on endothelial cells, alveolar cells, neutrophils, eosinophils, basophils, mast cells, monocytes, and lymphocytes, which are inhibited by corticosteroids. In 1995, we found that MCP-1 provokes mast cell aggregation and [3H]5HT-release in cultured mast cells. In another study, MCP-1 and RANTES revealed to have a potent chemoattractive effect on basophilic cells originating from the rat skin. In this inflammatory model, RANTES also attracted eosinophils and macrophages along with basophilic cells. The effect of RANTES on inducing HDC mRNA was dose dependent. MCP-1 and RANTES provoked histamine release in intradermal mast cells and prostaglandin D2 generation. These effects clearly show that RANTES and MCP-1 are mediators of acute inflammatory responses. In chronic inflammatory reactions, MCP-1 is also present as we show in a study recently published by our group. In this paper, we found that MCP-1, strongly mediates the recruitment of mononuclear cells in the granuloma formed by KMnO4. In addition, MCP-1 mediated a parasitic infection caused by Trichinella spiralis in mice. Our data strongly demonstrate that chemokines, such as RANTES and MCP-1, mediate acute inflammatory response.

Animals↗
PubMedDate not supplied

Nodular macroglossia with combined light chain and beta-2 microglobulin deposition in a long-term dialysis patient.

We describe a case in which nodular macroglossia, a very rare type of tongue involvement, was associated with the co-deposition of lambda light chain and beta-2 microglobulin fibrils in the tongue. The combined presence of two different amyloid fibrils did not lead to a more unfavourable clinical outcome. We believe that both these features often remain underdiagnosed and are in fact more frequent than reported. A careful clinical examination of the tongue together with serum immunofixation should be routine in all patients with dialysis-related amyloidosis in order to investigate the prevalence and type of tongue involvement and to rule out other types of amyloidosis. In all cases of suspected mixed amyloidosis, immunohistochemical characterization of fibrils should be carried out by electron microscopy.

Amyloidosis↗
PubMedDate not supplied

Nonparasitic cysts of the liver: laparoscopic treatment and long-term results.

BACKGROUND: In the current debate on the indications for the laparoscopic treatment of symptomatic simple hepatic cysts, we emphasize the importance of the exact indications, practicing in an area endemic for hepatic hydatidosis. 8 years ago we started treating laparoscopically the simple hepatic cysts and the polycystosis. Although the laparoscopic approach to parasitic hepatic cysts has been recently introduced, this method has to be the result of a conscious choice and with a presumptive diagnosis to support it. In fact, reviewing the literature on the subject, we realized how most of the intraoperative complications were due to an erroneous preoperative diagnosis, likely to be attributed to the infrequent observation of hepatic hydatid disease. Hence, it seems of primary importance to review the subject in light of the potential dangerous aspect of the laparoscopic approach. METHODS: From 1992 to 2000 we treated 38 cases of benign liver cystic disease (29 echinococcal cysts, 8 symptomatic simple cysts, 1 polycystosis). Due to the endemic nature of the disease in our territory, the preoperative diagnosis was very meticulous (ultrasonography, CT scan, MRI, serology...). Only 9 cases with a preoperative diagnosis of simple cyst or polycystosis were treated with laparoscopic wide fenestration, combined with cholecystectomy in three cases. The follow-up consisted of ultrasonography in the majority of cases and CT scan in 2. RESULTS: All the 9 laparoscopic cases were uncomplicated and no conversions to open procedures have been recorded. The final pathology confirmed the initial diagnosis in all cases. The follow-up ranged between 1 and 8 years and complete remission has been obtained. CONCLUSIONS: The results of this study demonstrate how a meticulous preoperative clinical evaluation can avoid intraoperative complications, making the laparoscopic approach to non-hydatid hepatic cystic disease safe and efficacious. Although laparoscopy is indicated in parasitic liver pathology, the technical approach is very different from the simple cystic disease. In the former, in fact, hepatic resection or pericystectomy are utilized, the results of which have been currently evaluated and compared with the open technique on a large scale on several ongoing trials.

Adult↗
PubMedDate not supplied

The results of the surgical treatment of 64 patients with thoracic and lumbar fracture.

A total of 64 patients surgically treated for vertebral fractures were evaluated clinically and radiographically after a mean time of 49.55 months (from 1 to 124). There were 50 males and 14 females. Mean age at the time of surgery was 40.67 years (from 17 to 71). Fractures were divided based on the Denis classification system: comminuted fractures: 45; fractures caused by flexion-distraction: 2; fracture-dislocation: 17; 31 of the fractures were localized at the lumbar level, 30 in the dorsal region, 3 at the dorsolumbar passage. Neurologic evaluation was carried out on admission and at follow-up using the Frankel classification system: type A: 22; type B: 13; type C: 7; type D: 6; type E: 16. 56.25% of the patients (36 cases) were classified as having multiple trauma. Of the 64 patients, 38 had reduction and stabilization within 6 hours of trauma, 26 were treated after a mean time of 2.7 days (from 1 to 6). Harrington-Luque stabilization was carried out in 5 patients, using the Hartshill rectangle in 59. The mean time for hospitalization was 27.68 days (from 9 to 91). Follow-up showed neurologic recovery in all of the patients operated on, with the exclusion of those classified as Frankel A, without sacral sparing. Despite the residual kyphosis and the final anatomic findings which were not always satisfactory, the methods used allowed us to obtain results that could be compared to those obtained by other means of fixation and more complex techniques.

Adolescent↗
PubMedDate not supplied

Allergen immunotherapy: an effective immune-modifier.

Allergen-specific immunotherapy (IT) consists in administering gradually increasing doses of an allergen extract to sensitive patients. This practice results in ameliorating symptoms associated with the subsequent exposure to the causative allergen. Presently, the lack of therapies which affect the pathogenesis of the disease make IT the only treatment that may improve the natural course of allergic diseases.

Journal Article↗
PubMedDate not supplied

Rat peritoneal mast cells release regulated upon activation normal T cell expressed and secreted (RANTES) after TNF-alpha activation.

Chemokines are a family consisting of at least ten distinct novel 8-10 kD cytokines. The cysteine-cysteine (C-C) chemokines are chemoattractant and activators for monocytes, T cells and mast cells. RANTES is the prototype of the C-C chemokine subfamily, purified from different sources with chemoattractant and activator properties. In this study we found that supernatants derived from TNF-alpha (scalar concentrations)-activated rat peritoneal mast cell cultures (5 x 10(5)/mL), incubated overnight, produced high levels of RANTES. This data describes an additional mode of generation of RANTES. Moreover, RANTES mRNA was not significantly produced in untreated cells, while it was dramatically increased by calcium ionophore A23187, LPS and TNF-alpha compared with the controls. These results underscore the importance of the presence of mast cells for the production of RANTES in the inflammatory process and contribute to an understanding of the mechanism by which RANTES profoundly affects inflammatory responses in vivo.

Animals↗
PubMedDate not supplied

Tumor imaging with carbon-11 labeled alpha-aminoisobutyric acid (AIB) in patients with malignant melanoma.

The potential usefulness of [C-11]-labeled alpha-aminoisobutyric acid (AIB) for tumor imaging has been demonstrated previously in our findings of increased tumor uptake with C-14-labeled AIB in human melanoma heterotransplants in nude mice, and subsequently, in a single case study using C-11 AIB to demonstrate the extent of metastases in patient with widespread malignant melanoma. We report here on the use of C-11 AIB in ten patients with metastatic or unresectable malignant melanoma. Five patients had intense tracer uptake at all known sites of tumor involvement. A sixth patient had good uptake in metastatic lesions in the shoulder and the pelvis, but did not demonstrate uptake within metastatic lesions in the lungs. Two patients had only minimal uptake over the tumor lesions while the two other patients had essentially normal studies. Further studies with C-11 AIB in patients with melanoma and other tumors are warranted.

Adult↗
PubMedDate not supplied

For an elective surgical management in lumbar intervertebral disc herniation. Experience of 25 years of surgery.

On the base of a wide clinical experiences, the Authors report some consideration about relationship between clinical findings and neuroradiological pictures (plain film, myelography, CT and NMR) of the lumbar vertebral and disc diseases. It's pointed out the useful aspect of each imaging technique that contribute to obtain the more complete informations about anatomy of the lesion; such considerations allows the surgeon to plain the more adequate surgical technique. The Authors think myelography, still today, is the investigation of choice in this kind of pathology.

Adult↗
PubMedDate not supplied

[Mucoceles of the paranasal sinus: report of 5 cases].

AA. report 5 cases of mucoceles that they have seen during a 5 years period; all the etiological factors that have been reported are present. Flogosis, trauma and neoplasm may create a mechanical obstacle to mucoid fluid flow; the intrasinusal pressure increases and erode the osseus wall and thus the mucoceles con herniate into adjacent structures.

Adult↗
PubMedDate not supplied

Effects of human interleukin-1 on natural killer cell activity: is fever a host defense mechanism for tumor killing?

Interleukin-1 (IL-1) represents a family of polypeptides with a wide range of biological activities. cDNA from two gene products has been cloned; there are probably more. The human IL-1 family plays an important role in the pathogenesis of many diseases and functions as a key mediator of host response to various infectious, inflammatory, neoplastic, and immunologic challenges. Recombinant mouse (pI 5) and recombinant human (pI 7) IL-1s are being used to confirm the multiple biological properties of IL-1s. Some IL-1 biological activities seem to be involved with mechanisms of host tumor killing. Incubating purified or recombinant human IL-1 with human peripheral blood mononuclear cells in the presence of IL-2 or interferon-alpha results in a synergistic enhancement of certain tumor cells. More recent results indicate that IL-1 exhibits direct cytotoxicity for tumor cells in vitro. The peripheral blood mononuclear cells of patients with tumors demonstrate decreased production of IL-1 when challenged with endotoxin and show a comparable decrease in natural killer activity; adding exogenous IL-1 reverses this defect in these patients. However, induction of hepatic acute-phase proteins such as serum amyloid A serves as a negative feedback since the amyloid protein suppresses natural killer activity. Moreover, natural killer cell activity in the presence of IL-1 or interferon-alpha is suppressed by incubating temperatures of 39 degrees C. This effect is not reversed by inhibitors of prostaglandin synthesis. IL-1 is clearly important to host defense against malignancy, but some aspects of IL-1 biology seem to exert a contrary influence.

Cytotoxicity, Immunologic↗
PubMedDate not supplied

Surgical treatment of vertebro-epidural neoplasms of the cervical tract via the anterior approach.

Fifteen cases of vertebral-epidural neoplasms of the cervical tract, treated surgically by the technique of longitudinal median somatotomy with inlay arthrodesis via the anterior approach are presented. Compression of the spinal anterior artery is eliminated by the wide anterior longitudinal exposition, which also creates a support for a possible second operation, either laminectomy or foraminotomy.

Adolescent↗
PubMedDate not supplied

Observations on some rare cases of vertebro-medullar malformations associated with tumors.

Three cases of complex vertebro-medullary malformations of the diastematomyelic type associated with dysembriogenetic tumors are presented. In the first case, a true diastematomyelia, associated with a teratoma of mixed histological structure, is described. In the second and third cases, diplomyelia associated with an epidermoid and a dermoid cyst respectively are reported.

Adult↗