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Biomedical subjects

S Seidenari

Publications and source records attributed to S Seidenari.

At least 91 records · Page 5Linked to original sources
PubMed1994

Echographic evaluation with image analysis of normal skin: variations according to age and sex.

In order to identify and characterize the sonographic variations between different age groups, 48 subjects, 24 aged 27-30, and 24 over 60, were studied with a 20-MHz B scanner on six skin sites. Images were evaluated by the instrument's standard programme and by a new image analysis software package enabling the characterization of steady structures or transitory functional aspects of skin reactions, by highlighting areas in which the echo amplitudes are included within selected values, and by calculating their extension. Three bands were selected as intervals of interest, respectively, highlighting hyporeflecting parts of the dermis, tissue reflecting with intermediate amplitude values and hyperreflecting epidermis and dermis. This method was employed to assess skin thickness, demonstrating its decrease in elderly skin, to characterize and quantify the hypoechogenic subepidermal band appearing in the elderly at volar and dorsal forearm skin, and to evaluate echogenicity of the upper and lower dermis. Our data show that there is a great regional variation in the behaviour of ultrasound reflection of elderly skin in respect to the skin of young subjects. However, a general trend can be identified, consisting in a shift from low-intensity ultrasound echoes, characteristic in the dermis of young subjects, to intermediate or high reflection amplitudes, which are more frequent in elderly skin. Thus, the echographic method provides two parameters for the evaluation of skin aging.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Reactivity to nickel sulfate at sodium lauryl sulfate pretreated skin sites is higher in atopics: an echographic evaluation by means of image analysis performed on 20 MHz B-scan recordings.

The aim of this study was to establish an objectively assessable procedure simulating simultaneous exposure to irritants and allergens in domestic and occupational environments, in order to evaluate differences in the reactivity to the combination of these substances in atopic and non-atopic nickel-sensitized subjects. Thirty-four nickel-sensitive patients, 20 of whom were affected by atopic dermatitis, underwent four patch tests with NiSO4 0.05% aq. on two adjacent sites of both volar forearms, with a 24-h application time. Two of the test sites were treated with sodium lauryl sulfate (SLS) 5% for 30 min, before application of the nickel sulfate preparation. Echographic recordings were performed by a 20-MHz B-scanner and processed by an image analysis program, providing a numerical representation of the picture data, based on the attribution of fictional values to the amplitudes of the echoes. The dermal inflammatory reaction was quantified by an amplitude band, marking the hypo-reflecting part of the dermis, whereas epidermal damage was assessed by a band highlighting the entrance echo. Pre-treatment with SLS of the skin area where nickel sulfate was subsequently applied greatly enhanced the allergic response at 24 and 72 h, both in subjects with atopic dermatitis and in subjects with allergic contact dermatitis. However, in atopics, the increase in the allergic reactivity after irritation of the skin was more pronounced both by clinical and by echographic evaluation. These observations stress the importance of the concurrent action of irritants and allergens in maintaining the dermatitis in atopics.

Adolescent↗
PubMed1994

Echographic evaluation with image analysis of histamine-induced wheals.

10 healthy, non-atopic women, aged 20-30, underwent histamine prick tests, performed in duplicate on the volar surface of the forearm with progressively increasing histamine concentration, from elbow to wrist on the left arm and from wrist to elbow on the right. Histamine wheal assessments were performed with the following methods at 5, 10, 15 and 20 min from challenge: planimetry for wheal area determination, A-scanning for skin thickness evaluation and echographic image analysis for assessing skin edema corresponding to the hypoechogenic area in the dermis. Wheal extension, skin thickness and edema of the dermis increase in time according to the histamine concentration. However, in response to the same concentration, regional variations consisting in greater wheal extension and dermis hypoechogenic areas were observed on proximal than on distal sites. Conversely, statistically significant differences were found between tests carried out on the right arm compared to those on the left regarding skin thickness. These variations have to be considered when interpreting data derived from pharmacological studies on the inhibition of histamine-induced reactions.

Adult↗
PubMed1993

Contact dermatitis and contact sensitization among enamellers and decorators in the ceramics industry.

126 enamellers and 64 decorators from 5 factories underwent dermatological and allergological examination using occupational test series in order to evaluate the prevalence of dermatitis and contact sensitization, and to identify the most important sensitizing substances. 48 workers (corresponding to 25.26% of the study population) were sensitized, with a total of 55 positive patch tests. Dermatitis was present in 22 workers, whereas 44 subjects claimed to have had skin lesions in the past. We found 17 positivities to specific substances: 7 to red iron oxide; 2 to antimony trioxide, manganese dioxide and maleic anhydride; and 1 to red copper oxide, cadmium chloride, vanadium pentoxide and sodium tripolyphosphate.

Allergens↗
PubMed1993

Assessment of topical corticosteroid activity on experimentally induced contact dermatitis: echographic evaluation with binary transformation and image analysis.

A new echographic evaluation method employing a B scanner and a dedicated software (Dermavision 2D, Cortex Technology, Hadsund, Denmark) was used in assessing the potency of three different corticosteroids. Experimental lesions were induced by patch tests with nickel sulfate 5% in petrolatum in 10 sensitized subjects and treated with two medications of different steroids (clobetasol propionate, fluocinolone acetonide or clobetasone butyrate) performed 16 and 40 h after the application of the nickel patch tests. Clinical and echographic evaluations were carried out at the beginning of the experiment and 64 h after the induction of the reactions. After obtaining echographic images, these were processed by software, enabling the selection of amplitudes of interest, the highlighting of parts of images and their assessment by a value corresponding to the number of pixels (picture elements). For evaluations a low reflecting band was chosen, marking edema and inflammatory infiltration. At positive patch test sites we observed a progressive increase in the number of low reflecting pixels, in accordance with the intensity of the reaction. Therapeutic response was assessed as the difference between values of treated and untreated test sites. The rank order of the efficacy of test substances as determined echographically was identical to the rank order generally accepted for these steroids. This evaluation method of topical corticosteroid activity could be usefully employed besides traditional evaluation methods.

Administration, Topical↗
PubMed1992

Cutaneous reactivity to allergens at 24-h increases from the antecubital fossa to the wrist: an echographic evaluation by means of a new image analysis system.

To establish the existence of regional variations in response to allergens, we performed patch tests with nickel sulfate 5% pet. at 4 different sites on the volar forearm skin in 17 nickel-sensitive women, aged from 18 to 45 years. After a 24-h application, patch tests were removed and evaluated both by clinical scoring and by means of a 20 MHz ultrasound B scanner. Recorded echographic images referring to uninvolved skin and to positive test sites were evaluated by a traditional image analysis method for the determination of skin thickness. Furthermore, they were processed by software which ascribes arbitrary values to the amplitude levels of the echoes and enables quantification of the pixels, (the smallest elements in a visual display with controllable colour and brightness) forming objects reflecting within a selected amplitude band. Thus, we demonstrated an increase in thickness of uninvolved skin at distal sites and a greater reactivity at 24 h to patch tests in skin areas near to the wrist crease, as evidenced by a greater increase in pixel and in thickness values at distal sites. From our data, we have a clear indication for the use of rotating patterns or symmetrical sites in quantitative and comparative investigations concerning the evaluation of contact allergy on volar forearm skin.

Adolescent↗
PubMed1992

B-scanning evaluation with image analysis of psoriatic skin.

Ten psoriatic plaques from different subjects were investigated by 20 MHz ultrasound B scanning. Lesions were evaluated before therapy, and after 7 and 15 days of topical treatment with anthralin. Recordings from lesional skin were compared with those from clinically non-involved contralateral skin. Images were assessed by means of a new image analysis program, allowing the conversion of the B-scan image color scale into a numerical amplitude scale, the selection and highlighting of amplitude bands, and the quantification of objects reflecting in a definite amplitude range. B-scanning evaluation of the psoriatic plaque revealed a thickening of the epidermis and dermis, the presence of parallel acoustic shadows in the dermis, and a characteristic hypo-echogenic band corresponding to the papillary dermis. Image processing allowed an exact quantification of the progressive reduction in thickness of the epidermis and dermis and of the hypo-echogenic band observed at skin sites which had been treated with topical substances. Thus, the echographic method with image analysis allows the evaluation of three different parameters of response to topical treatment of psoriatic skin.

Adult↗
PubMed1992

B scanning evaluation of allergic reactions with binary transformation and image analysis.

In order to characterize and quantify allergic skin reactions, 12 nickel sensitized women aged 18 to 45 underwent 5 patch tests with nickel sulfate in petrolatum at the following concentrations: 0.5, 1, 2, 3 and 5%. The tests, performed on volar forearm skin, were removed after a 24-h application. B scanning evaluations were carried out at the beginning and at 24, 48 and 72 h after patch test application using Dermascan C (Cortex Technology, Hadsund, Denmark). After obtaining echographic images, there were processed by a dedicated programme (Dermavision 2D, Cortex Technology, Hadsund, Denmark) enabling the selection of amplitudes of interest and the transformation into a binary colour system. By attributing one colour to a selected amplitude band, part of an image can be highlighted and assessed by a value corresponding to the number of pixels (picture elements). For the evaluation of the images, 2 bands were chosen. The first, ranging from 201 to 255 is able to highlight hyper-reflecting parts of the pictures (epidermis, lower part of the dermis); the second, ranging from 0 to 30, marks the hypo-echogenic part of the tissue, which is the site of inflammation. This method showed a progressive increase in the number of low reflecting pixels according to the nickel patch test concentration and to the elapsing of time. On the contrary, at 24 h there was a decrease in pixel values concerning the hyper-reflecting band. This evaluation method proved useful in assessing the intensity of patch test responses.

Adolescent↗
PubMed1992

B scanning evaluation of irritant reactions with binary transformation and image analysis.

In order to characterize and quantify irritant skin reactions, 12 women aged 18 to 45 underwent 5 patch tests with sodium lauryl sulfate at the following concentrations: 0.5, 1, 2, 3 and 5%. The tests, applied on volar forearm skin, were removed after a 24-h application. Evaporimetry and B scanning were carried out at the beginning and at 24, 48 and 72 h after patch test application. Echographic recordings were performed by Dermascan C (Cortex Technology, Hadsund, Denmark). After the acquisition, the echographic images were processed by a dedicated software (Dermavision 2D, Cortex Technology, Hadsund, Denmark) enabling the selection of amplitudes of interest and the transformation into a binary colour system. By attributing one colour to a selected amplitude band, part of an image can be highlighted and assessed by a value corresponding to the number of pixels (picture elements). For the evaluation of the images, 2 bands were chosen. The first, ranging from 201 to 255 is able to highlight hyperreflecting parts of the pictures (epidermis, lower part of the dermis); the second, ranging from 0 to 30, marks the hypo-echogenic part of the tissue, which is the site of inflammation. The evaluation by means of the 201-255 amplitude band showed a marked decrease of the echogenicity of the epidermis which was more pronounced at 24-h determinations and for higher concentrations of sodium lauryl sulphate (SLS), whereas the increase in pixel numbers, shown by the 0-30 band, was slight and apparent only for high SLS concentrations. Echographic data and transepidermal water loss (TEWL) values showed a good correlation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Positive patch tests to whole mite culture and purified mite extracts in patients with atopic dermatitis, asthma, and rhinitis.

Patch tests with Dermatophagoides were carried out by different authors on patients with atopic dermatitis (AD) employing methods varying both in the type of allergen and in the way of performing the test. In order to examine and compare different methods and various allergenic materials and to define better the indications for this test, we performed patch tests with whole mite culture or purified mite extracts on 72 patients with AD, 40 subjects with mucosal atopy, and 32 healthy volunteers, employing different techniques of application. Positive results were obtained in 51.5% of patients with AD with specific IgE to Dermatophagoides, in 43.6% of patients with AD without this specific IgE and in 40% of subjects affected by mucosal atopy and having specific IgE to Dermatophagoides. From a technical point of view the simple application of the allergenic material on healthy skin gave the best results. Our data show that patch tests with Dermatophagoides extracts could contribute to a better immunoallergologic characterization both of patients with AD and patients with mucosal atopy.

Adolescent↗
PubMed1991

Ultrasound B scanning with image analysis for assessment of allergic patch test reactions.

Assessment of patch test results has been performed visually and using ultrasound in the B mode. A positive test site has a typical ultrasonographic appearance, presenting a uniform hypoechogenic area in the dermis. In this zone, the mean amplitude of ultrasound reflection peaks decreases, and the extension of this area increases, together with the intensity of the eczematous reaction. A close correlation has been shown between visual scoring, amplitude decrease and surface increase of the hypoechogenic area. This technique seems to provide a reproducible system for the evaluation of patch tests.

Adolescent↗
PubMed1991

Contact sensitization to textile dyes: description of 100 subjects.

We have described 100 subjects sensitized to textile dyes. Of these, 16 had clinically been suspected of having a textile dermatitis from among 1145 patients referred for patch testing. 41 patients were identified from among 861 consecutive subjects tested with the GIRDCA (Italian Research Group on Contact and Environmental Dermatitis) standard series supplemented with 4 disperse dyes (Disperse Blue 124, Disperse Red 1, Disperse Yellow 3, Disperse Orange 3). The remaining 43 patients were identified from among 746 subjects tested with the GIRDCA standard series, supplemented with the 4 disperse dyes mentioned above and a further series of 12 other textile dyes. The clinical picture was extremely variable: most patients had a typical eczematous dermatitis, but we also observed persistent erythematous-wheal-type reactions, a transient urticarial dermatitis and an erythema-multiforme-like eruption. Among these textile dyes, Disperse Blue 124 caused most reactions. With the addition of the 4 disperse dyes to the GIRDCA standard series, we identified 4.8% sensitized to textile dyes, a much higher figure than the 1.4% observed among patients being patch tested on the basis of their history and the clinical findings; the addition of a further 12 textile dyes to the series further increased the detection rate to 5.8%. We stress the importance of routinely patch testing with textile dyes, which can help to elucidate the cause of certain kinds of atypical dermatitis.

Adolescent↗