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P Natali

Publications and source records attributed to P Natali.

At least 19 recordsLinked to original sources
PubMed2004

Alternaria spores at different heights from the ground.

BACKGROUND: Alternaria tenuis (Alt) is one of the main allergens in pediatric age. In temperate climates, airborne Alt spores are detectable from May to November with peaks in late summer and autumn. Sensitized children display symptoms even in the absence of airborne Alt spores. Alt spore concentration, as well as pollen, is usually detected by fixed devices located on the roof of a building at a height of 10-20 m. The aim of the current study is to find out whether ground-level (50 cm) Alt spore concentrations are different from those at roof-top level, even during low-concentration periods. METHODS: Alt samples were taken simultaneously using a Hirst fixed volumetric collector (FVC) placed on a 15 m-high roof and by a portable volumetric collector (PVC). Firstly, the results of FVC and PVC, both placed on the roof-top, were compared to verify the correlation coefficient of the two samplers. Subsequently, the PVC was placed 50 cm above the ground in a courtyard (30 samplings) and in private green areas (50 samplings). The results were compared by statistical analysis (Student's t-test or K-S test). RESULTS: The values of the 20 samples taken jointly in summer time (FVC 195 +/- 134 spores/m(3); PVC = 134 +/- 131 spores/m(3)) showed a good correlation between the two samplers (r = 0.850; P < 0.01), with a correction factor equal to 1.177. 1. Thirty samples obtained in summer and winter when the PVC was positioned in an enclosed courtyard directly below the FVC showed no significant difference (PVC, 181 +/- 194 spores/m(3); FVC, 152 +/- 145 spores/m(3); P = 0.221). 2. Fifty samples taken by PVC placed in private green areas in a low-concentration period, showed significantly higher concentrations than by FVC: PVC, 531 +/- 925 spores/m(3); FVC, 25 +/- 51 spores/m(3) (K-S test: P < 0.0001). In particular, 33 samples taken in winter when Alt counts by FVC were <10 spores/m(3) still demonstrated highly significant differences: PVC, 398 +/- 961 spores/m(3); FVC, 2.0 +/- 2 spores/m(3) (K-S test: P < 0.0001). CONCLUSION: Our results lead to the conclusion that Alt spore concentration is significantly higher at ground level in the presence of vegetation, even when the spore concentration is very low (<10 spores/m(3)). These results further suggest that the individual's exposure to Alt, especially in the case of children, is underestimated by samples taken at roof-top level by FVC.

Air Pollutants↗
PubMed2003

Thyroid abscess associated with a substernal goiter. Case report.

An abscess associated with an intrathoracic goiter is an extremely rare condition. The authors report a case of a thyroid abscess complicated by acute dyspnea and asphyxia in a patient of geriatric age with a substernal goiter. Surgical therapy was necessary to obtain a correct diagnosis and an effective treatment.

Abscess↗
PubMed2003

Descending necrotizing mediastinitis. Diagnosis and surgical treatment.

AIM: Descending necrotizing mediastinitis (DNM) is an unusual and severe disease with a high mortality rate. Surgical management remains controversial. Our investigations reviews the most effective surgical treatment in the management of this rare pathology. METHODS: Seven patients with DNM and treated over a 20-year period are reported. All patients were evaluated according to the classification suggested by Endo et al. of the degree of mediastinal diffusion, based on CT scan findings. Five patients underwent combined cervical drainage and thoracotomy, 2 patients were treated with cervical drainage alone. RESULTS: The outcome was favorable in 5 patients, 4 treated with a combined cervical and thoracic approach and 1 with a cervical approach alone. Two patients that underwent a combinated cervical and thoracic approach alone, died of septic shock. Overall mortality rate was 28.5%. CONCLUSION: Early diagnosis and early, aggressive surgical treatment are required to improve the poor prognosis of DNM. Although a unique surgical management is still not completely accepted, we state, in agreement with other authors, a wide approach consisting of a cervical drainage and mediastinotomy in case of upper mediastinitis and a combined cervical and thoracic approach in case of lower mediastinitis. In the course of thoracotomy a wide excision of necrotic and particularly fat mediastinal tissue is needed, to avoid a recurrent infection. A continuous cervico-mediastinal irrigation system is suggested during the postoperative period.

Adult↗
PubMed1993

Differential effect of human and murine polyclonal and monoclonal antisera on TNF-alpha production by human monocytes.

The capacity of human and murine polyclonal and monoclonal antibodies to inhibit lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha (TNF-alpha) release from human monocytes was investigated. Human pooled immunoglobulin G (IVIG), human IgM monoclonal antibody (HA-1A) directed against the lipid A moiety of LPS, and murine IgG monoclonal antibody (MT-1F) raised in mice against antibiotic-treated Escherichia coli O6:K- were either added simultaneously with LPS to monocytes or preincubated for 1 h at 37 degrees C before being added to monocytes. TNF-alpha content in the monocyte supernatants was then tested. Simultaneous addition of increasing concentrations of IVIG (from 0.3 to 2.5 mg/ml) and 10 micrograms/ml of LPS to monocytes induced an enhanced release of TNF-alpha by monocytes in a dose dependent fashion. Preincubation of IVIG with LPS abolished the additive effect, but did not inhibit LPS-induced TNF-alpha release by monocytes. The simultaneous addition of LPS and HA-1A to monocytes had no additive effect nor did it inhibit TNF-alpha release. On the other hand, inhibition of TNF-alpha release was observed when HA-1A was preincubated with LPS before being added to monocytes. In all instances MT-1F inhibited TNF-alpha release when the monocytes were stimulated with smooth type LPS, but not with LPS isolated from rough mutants.

Animals↗
PubMed1990

Differential expression of intercellular adhesion molecule 1 in primary and metastatic melanoma lesions.

Immunochemical studies have shown that the monoclonal antibody (MoAb) CL203.4, elicited with immune interferon treated cultured human melanoma cells Colo 38, recognizes intercellular adhesion molecule 1 (ICAM-1). The determinant defined by MoAb CL203.4 is distinct and spatially distant from that defined by anti-ICAM-1 MoAb RR1/1, which had been elicited with Epstein-Barr virus-transformed B-lymphocytes from a lymphocyte function associated antigen 1 deficient patient. Immunohistochemical testing with MoAb CL203.4 of surgically removed lesions of melanocyte origin has shown a markedly lower reactivity with benign than with malignant lesions. Among the latter, a higher percentage of metastatic than of primary lesions was stained by MoAb CL203.4. The higher expression of ICAM-1 in metastases than in primary lesions is unique to melanoma, since no difference was found in its distribution in primary and metastatic lesions of a variety of malignancies of different embryological origin. Reactivity with MoAb CL203.4 of primary lesions removed from patients with stage I melanoma showed a highly significant correlation with the lesion thickness and with the clinical course of the disease. The disease free interval in patients without detectable reactivity of their primary lesion with MoAb CL203.4 was significantly (P = 0.004) longer than that of patients whose primary lesion was stained with MoAb CL203.4. These results suggest that ICAM-1 may be a useful marker in the analysis of the molecular mechanism underlying the association between lesion thickness and clinical course of the disease.

Adolescent↗
PubMed1988

Accessory cell function of human melanoma cells in mitogen-induced T cell proliferation.

Six out of eight human melanoma cell lines were found to be able to function as accessory cells in PHA-induced proliferation of autologous and allogeneic T cells. The accessory cell function of the melanoma cell lines appears to be similar to that of monocytes, requires the presence of viable cells, and does not correlate with the cell surface binding sites for PHA and with the level of expression of HMW-MAA and of HLA Class I antigens. HLA Class II antigens do not appear to play a major role in these phenomena, since there is no relationship between level of expression of HLA Class II antigens and accessory cell function of melanoma cells. Furthermore, addition of anti-HLA Class II monoclonal antibodies does not affect proliferation of T cells stimulated with PHA in the presence of melanoma cells with accessory cell function. Although melanoma cells exert accessory cell function, functional and immunological assays did not detect IL-1 in the spent medium of the melanoma cell lines. Furthermore, Northern blotting analysis with IL-1 alpha and IL-1 beta probes did not detect IL-1-specific mRNA in melanoma cell lines. These results suggest that PHA-induced proliferation of T cells in the presence of melanoma cells can bypass the requirement for IL-1 or utilizes factors other than IL-1.

Antigen-Presenting Cells↗
PubMed1986

Gene products of the HLA-D region in normal and malignant tissues of nonlymphoid origin.

Indirect immunofluorescence staining with monoclonal antibodies has shown a differential distribution of HLA-DR, DQ, and DP antigens in normal tissues of nonlymphoid origin. The distribution of HLA-DP antigens is similar to that of HLA-DR antigens, while that of HLA-DQ antigens is more restricted. Malignant transformation of cells of nonlymphoid origin may be associated with the appearance of the gene products of the HLA-D region. HLA-DR antigens appear more frequently than the other two types of HLA class II antigens and HLA-DP antigens more frequently than HLA-DQ antigens. Differential expression of the gene products of the HLA-D region was also found in autologous metastases removed from different anatomic sites from patients with melanoma. The HLA class II phenotype of surgically removed malignant lesions did not correlate with the degree of differentiation of tumor cells and/or with the expression and/or cellular distribution of HLA class I antigens. Furthermore, in melanoma lesions, no relationship was found between the HLA class II phenotype and the expression of 3 membrane bound and 1 cytoplasmic melanoma associated antigen recognized by monoclonal antibodies. The functional significance and the practical implications of the differential expression of the gene products of the HLA-D region by tumor cells are discussed.

Antibodies, Monoclonal↗
PubMed1985

Distribution of a cross-species melanoma-associated antigen in normal and neoplastic human tissues.

In previous studies the monoclonal antibody (MoAb) M2590 elicited in C57/BL6 mice with the syngeneic melanoma cell line B16 has been shown to recognize a 31K glycoprotein expressed by human melanoma cell lines. The present study has shown that the MoAb M2590 cross-reacts with surgically removed benign and malignant lesions of melanocyte origin. The reactivity pattern of the MoAb M2590 with these lesions is different from that of the anti-high-molecular weight-melanoma associated antigen (HMW-MAA) MoAb 225.28S, of the anti-115K MAA MoAb 345.134S, and of the anti-100K MAA MoAb 376.96S, which were elicited with human melanoma cell lines. In particular, the MoAb M2590 reacts with blue nevi. The MoAb M2590-defined MAA, like other types of MAA, is heterogeneous in lesions removed from different patients, in autologous lesions removed from different anatomic sites, and in cells within a lesion. The distribution of the MoAb M2590-defined MAA in normal tissues and in tumors of nonmelanocyte origin is broader than that of the HMW-MAA, but is similar to that of the 115K MAA and of the 100K MAA. The results of this investigation suggest that immunization with xenogeneic melanoma cells may broaden the range of specificity of antihuman MAA MoAbs and provide information about the phylogenetic evolution of MAAs.

Adult↗
PubMed1985

Analysis of the interaction between a human high molecular weight melanoma-associated antigen and the monoclonal antibodies to three distinct antigenic determinants.

The restricted tissue distribution and the limited heterogeneity that appear in melanoma lesions of the high M.W. melanoma-associated antigen (HMW-MAA) suggest that this antigen may be an appropriate marker for radioimaging, and a useful target for immunotherapy in patients with melanoma. Therefore, in this study we analyzed other characteristics that are important in the selection of reagents for radioimaging and immunotherapy purposes. The affinities of the monoclonal antibodies (MoAB) 149.53, 225.28S, and 763.74T to distinct determinants of the HMW-MAA were found to be at least 1 X 10(8) mol/L. Furthermore, the effects of the concentrations of unlabeled MoAb on the dissociation rates suggest that the binding of MoAb 149.53 and 225.28S to melanoma cells (Colo 38) is preferentially bivalent, whereas that of MoAb 763.74T is preferentially univalent. These results suggest that the latter MoAb is the reagent of choice for assays that make use of soluble HMW-MAA, whereas the former two are the reagents of choice for assays with membrane-bound HMW-MAA, such as imaging with radiolabeled MoAb. The density of the HMW-MAA on cultured Colo 38 melanoma cells appears to be in the range of approximately 5 X 10(6) molecules/cell. The HMW-MAA was not susceptible to MoAb-mediated modulation under a variety of experimental conditions that included various concentrations of modulating MoAb, different incubation times, the use of an anti-mouse Ig antiserum, and the relaxation of equilibrium by diluting cells in MoAb-free medium. These results indicate that the HMW-MAA and the available corresponding MoAb meet the criteria to be reagents for radioimaging and immunotherapy in patients with melanoma.

Animals↗
PubMed1985

Heterogeneous expression of melanoma-associated antigens and HLA antigens by primary and multiple metastatic lesions removed from patients with melanoma.

Indirect immunofluorescence staining with a large battery of monoclonal antibodies of primary and autologous metastatic lesions removed from seven patients with melanoma has detected heterogeneity in the expression of various types of melanoma-associated antigens (MAAs), of distinct determinants of the high molecular weight melanoma-associated antigen (HMW-MAA), of the two subunits of Class I HLA antigens, and of the gene products of the HLA-D region. Among the 10 MAAs tested, the HMW-MAA had the highest frequency and the Mr 87,000 MAA the lowest. Furthermore, the HMW-MAA displayed the lowest heterogeneity. These findings, in conjunction with the restricted tissue distribution of the HMW-MAA, its lack of susceptibility to antibody-mediated modulation, and the high affinity of the available anti-HMW-MAA monoclonal antibodies, indicate that this antigen may be a useful marker for radioimaging and immunotherapy in patients with melanoma. The common acute lymphoblastic leukemia antigen was detected only in five lesions. Class I HLA antigens were detected in a larger number of lesions than HLA-DR antigens, which had a significantly higher frequency than HLA-DQ antigens. The degree of antigenic heterogeneity did not appear to correlate with the histopathological features of the lesions and/or with the clinical course of the disease. The results of the present study indicate that immunodiagnostic and immunotherapeutic approaches to melanoma should rely on the use of combinations of monoclonal antibodies to distinct MAAs.

Animals↗
PubMed1982

[Hypokalemic myopathy in arterial hypertension].

Three cases of arterial hypertension and severe hypokaliemia are reported; in two cases an acute rhabdomyolisis was also observed. The syndrome was iatrogenic in two cases depending on the licorice eating and the combined use of diuretics and a 9-alpha-fluoroprednisolone-containing nasal spray in one patient, and on a long-term use of the same nasal decongestant in the other. In the patient 2 the persistence of low PRA and aldosterone levels seems to indicate an excess of mineralcorticoid activity other than aldosterone. The syndrome of factitious mineralcorticoid excess should, therefore, be considered in the differential diagnosis of arterial hypertension with hypokaliemia; the risks of a long-term administration of steroid-containing nasal sprays, responsible of serious side effects, should also be stressed.

Adult↗
PubMed1981

Malignant lentigo-melanoma--a comparative histological and electron microscopy study.

We examined, by light and electron microscopy, three cases of malignant lentigo, one of which was in the vertical growth phase. The purpose of our work was to compare the diverse patterns between superficial spreading melanoma and malignant lentigo. The observations suggest the following major findings: 1) the cells of malignant lentigo differ from normal melanocytes, and in the same specimen they differ from one another; 2) in malignant lentigo, melanosomes at stage II-IV are visible; and 3) in spreading melanoma, the melanosomes do not attain complete maturation. These morphological features explain the different behaviour of these two types of tumors.

Cell Nucleus↗
PubMed1981

Unchanged antigenic properties of a nuclear non-histone protein during phylogenesis.

The phyletic distribution of Sm antigen in eukaryotes has been investigated by means of immuno-chemical techniques. This nuclear antigen, which is an acidic glycoprotein of about 7S with DNA binding ability, is present in all organisms examined. Such evidence suggests a very slow evolutionary rate for at least the antigenic determinant(s) of the Sm antigen.

Animals↗