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S Borelli

Publications and source records attributed to S Borelli.

At least 19 recordsLinked to original sources
PubMed1999

Dosimetry of Gamma Knife and linac-based radiosurgery using radiochromic and diode detectors.

In stereotactic radiosurgery the choice of appropriate detectors, whether for absolute or relative dosimetry, is very important due to the steep dose gradient and the incomplete lateral electronic equilibrium. For both linac-based and Leksell Gamma Knife radiosurgery units, we tested the use of calibrated radiochromic film to measure absolute doses and relative dose distributions. In addition a small diode was used to estimate the relative output factors. The data obtained using radiochromic and diode detectors were compared with measurements performed with other conventional methods of dosimetry, with calculated values by treatment planning systems and with data prestored in the treatment planning system supplied by the Leksell Gamma Knife (LGK) vendor. Two stereotactic radiosurgery techniques were considered: Leksell Gamma Knife (using gamma-rays from 60Co) and linac-based radiosurgery (LR) (6 MV x-rays). Different detectors were used for both relative and absolute dosimetry: relative output factors (OFs) were estimated by using radiochromic and radiographic films and a small diode; relative dose distributions in the axial and coronal planes of a spherical polystyrene phantom were measured using radiochromic film and calculated by two different treatment planning systems (TPSs). The absolute dose at the sphere centre was measured by radiochromic film and a small ionization chamber. An accurate selection of radiochromic film was made: samples of unexposed film showing a percentage standard deviation of less than 3% were used for relative dose profiles, and for absolute dose and OF evaluations this value was reduced to 1.5%. Moreover a proper calibration curve was made for each set of measurements. With regard to absolute doses, the results obtained with the ionization chamber are in good correlation with radiochromic film-generated data, for both LGK and LR, showing a dose difference of less than 1%. The output factor evaluations, performed using different methods, are in good agreement with a maximum difference of 1.5% for all field sizes considered (LGK and LR) except the 4 mm helmet used in the LGK unit. In this case, differences exist between diode and radiochromic film measurements and both detectors show data values larger than the prestored OF value of 0.80. Dose profiles measured by radiochromic film and calculated are in excellent agreement for both LGK and LR with a maximum deviation of less than 1.0 mm, when full widths of the dose profiles at 20%, 50%, 80% levels are considered. When external photon beams are used in stereotactic radiosurgery, the 'well selected' radiochromic films are very accurate detectors both for relative and absolute dosimetry. The experimental results, obtained using both radiochromic and diode detectors, show that the 4 mm helmet relative output factor could be underestimated.

Film Dosimetry↗
PubMed1998

A human-SCID mouse model for allergic immune response bacterial superantigen enhances skin inflammation and suppresses IgE production.

Chronic skin colonization with Staphylococcus aureus is a well-known feature in atopic dermatitis. The aim of this study was to develop a human-SCID mouse model to analyze the possible role of bacterial superantigens in human allergic immune responses under in vivo conditions. SCID mice were reconstituted with peripheral blood mononuclear cells (between 2 and 9 x 10(7) cells per mouse) from atopic dermatitis patients sensitized to house dust mite allergen (Der p). Total and Der p specific antibody production required the following conditions: (i) injection of Der p; (ii) presence of CD14+ antigen-presenting cells; and (iii) IL-4 as shown by the inhibitory effect of human soluble IL-4 receptor on immunoglobulin E production. This model was used to study the immunomodulatory effects of the superantigen staphylococcal enterotoxin B in comparison with Der p. In intraperitoneally reconstituted human-SCID mice, topical treatment was ineffective in inducing skin inflammation. Therefore, additionally to intraperitoneal transfer, peripheral blood mononuclear cells from atopic donors were also injected intradermally. Such reconstituted SCID mice were then exposed via the skin to either Der p, staphylococcal enterotoxin B, or a combination of both. Maximal effects on epidermal inflammation and dermal T cell infiltration were obtained with staphylococcal enterotoxin B and Der p. Staphylococcal enterotoxin B alone was less effective and Der p only stimulated dermal T cell infiltration. These findings support the hypothesis that bacterial superantigens can act as trigger factors in allergic skin inflammation.

Administration, Topical↗
PubMed1998

Valaciclovir for the suppression of recurrent genital herpes simplex virus infection: a large-scale dose range-finding study. International Valaciclovir HSV Study Group.

A randomized, double-blind study of valaciclovir for suppression of recurrent genital herpes was conducted among 1479 immunocompetent patients. Patients were randomized to receive valaciclovir (250 mg, 500 mg, or 1 g once daily, or 250 mg twice daily), acyclovir (400 mg twice daily), or placebo, for 1 year. All valaciclovir dosages were significantly more effective than placebo at preventing or delaying recurrences (P < .0001). There was a dose-response relationship (P < .0001) across the once-daily valaciclovir regimens. Twice-daily valaciclovir and acyclovir were similar in effectiveness. Subgroup analysis showed that patients with a history of < 10 recurrences per year were effectively managed with 500 mg of valaciclovir once daily. One gram of valaciclovir once daily, 250 mg of valaciclovir twice daily, or 400 mg of acyclovir twice daily were more effective in patients with > or = 10 recurrences per year. Safety profiles of all treatments were comparable. Thus, valaciclovir is highly effective and well tolerated for suppression of recurrent genital herpes. Once-daily regimens offer a useful option for patients who require suppressive therapy for management of genital herpes.

Acyclovir↗
PubMed1998

Sensitization and development of allergic contact dermatitis caused by a single contact with an electrosurgical grounding plate containing acrylates.

Acrylates are known as potent sensitizers which can cause sensitization even during patch testing. A single exposure to concentrated acrylates can induce primary sensitization and contact dermatitis. Here we describe a 50-year-old man who developed contact dermatitis at the site of an electrosurgical grounding plate 2 weeks after orthopedic surgery. Patch testing revealed positive reactions to the electrosurgical plate and its components hydroxyethyl acrylate and hydroxyethyl methacrylate. As the patient has never had contact with acrylate-containing materials before, there is a high probability of primary sensitization by a single contact with the grounding plate during surgery.

Acrylates↗
PubMed1997

Immunohistochemical analysis of procathepsin L and cathepsin B in cutaneous Kaposi's sarcoma.

BACKGROUND: The expression of the proteinases cathepsins L and B are induced in tumors by malignant transformation, growth factors, and tumor promoters suggesting they play an important role in tumor invasion and metastasis. METHODS: By immunohistochemistry, procathepsin L and cathepsin B were studied in patients with Kaposi's sarcoma (KS). Formalin-fixed and paraffin-embedded tissues from 29 cases of KS (AIDS-associated KS, n = 24; non-AIDS-associated KS, n = 5) were immunolabeled with the polyclonal antibody directed against procathepsin L and the antisera directed against cathepsin B. RESULTS: Normal epidermis, eccrine sweat glands, and hair follicle expressed both cathepsins. We also found a positive staining for procathepsin L in normal blood vessels. In both "angiomatous" and "fibroblastic" lesions of KS no expression of these enzymes was observed. CONCLUSIONS: These findings support the hypothesis of a benign autochthonous origin of the lesions, such as a hyperplasia.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Valaciclovir versus aciclovir in patient initiated treatment of recurrent genital herpes: a randomised, double blind clinical trial. International Valaciclovir HSV Study Group.

OBJECTIVE: To compare the efficacy and safety of twice daily valaciclovir with five times daily aciclovir in the treatment of an episode of recurrent genital herpes simplex virus (HSV) infection in immunocompetent individuals. METHODS: 739 patients with a history of recurrent genital HSV infection received either oral valaciclovir (500 mg twice daily) or aciclovir (200 mg five times daily) for 5-days for treatment of their next recurrent episode in a controlled, randomised, double blind trial. Patients self initiated therapy at the first signs and/or symptoms of the HSV recurrence, then were assessed in clinic on five occasions over 7 days, and twice weekly thereafter until lesions had healed. Safety was evaluated through adverse experience reports and haematology and biochemistry monitoring. RESULTS: No significant differences were detected between valaciclovir and aciclovir for the primary endpoint, the duration of all signs and symptoms which included lesion healing and pain/discomfort. The hazard ratio [95% confidence interval] for valaciclovir v aciclovir was 0.93 [0.79, 1.08]. Lesion healing time was similar in each treatment group (hazard ratio valaciclovir v aciclovir 0.96 [0.80, 1.14]). The odds ratio of valaciclovir v aciclovir in preventing the development of vesicular/ulcerative lesions was 1.08 [0.82, 1.42]. Percentages of patients in whom all HSV cultures were negative were similar in the valaciclovir and aciclovir groups at 59% and 54% respectively; for patients having equal to or more than one positive culture result after treatment initiation, cessation of virus shedding was similarly rapid for the two treatments (hazard ratio 0.98 [0.75, 1.27]). The safety profiles of valaciclovir and aciclovir were comparable with adverse experiences being infrequent and generally mild. CONCLUSION: This study has demonstrated that valaciclovir 500 mg twice daily is equivalent in efficacy to aciclovir 200 mg five times daily as episodic treatment of recurrent genital HSV infection. Valaciclovir maintains the established efficacy and safety of aciclovir but offers a much more convenient twice daily dosing regimen.

Acyclovir↗
PubMed1996

[Detection of tyrosinase mRNA using reverse transcription/polymerase chain reaction with fine needle punctures of melanoma metastases].

Tyrosinase mRNA produced by melanoma cells can be detected by reverse transcriptase-polymerase chain reaction (rt-pcr) with fine-needle tissue punctures. Fine-needle punctures from six suspected skin and lymph node metastases in three patients with malignant melanoma were analysed via rt-pcr for tyrosinase mRNA. All the suspected metastases were surgically removed and histologically examined separately. In each case the rt-pcr results and the histological diagnosis corresponded. This less invasive and highly sensitive method could prove to be a useful alternative in the diagnosis of melanoma metastasis.

Aged↗
PubMed1996

[Effect of single UVA and UVB irradiation on the surface composition and viscoelastic properties of skin in vivo].

The present study was designed to evaluate the effects of single irradiation either with UVA (dosage: 50 J/ cm2) or UVB (dosage: 1 MED) on surface structure and viscoelastic properties of human skin. Biophysical measurements by means of profilometry and cutometry were carried out on normally sunprotected skin areas directly before and 24 hours after irradiation. UVA induced neither measurable changes in skin surface structure (expressed by the profilometrically calculated parameters of roughness Ra and RzDIN and the parameter Wt reflecting depths of furrows) nor in its viscoelastic properties (expressed by the cutometrically calculated ratio Uv/Ue reflecting viscosity and the ratio Ur/Uf reflecting biological elasticity). However, a single erythemogenic dose of UVB radiation was followed by significant increase in the depths of furrows, increase in viscosity and decrease in biological elasticity.

Adolescent↗
PubMed1995

[Overlap of Sjögren-lupus erythematosus syndrome].

Patients with anti-SSA(Ro)-positive Sjögren's syndrome (SS)/lupus erythematosus (LE) overlap are a immunogenetically, serologically and clinically homogeneous group; what they have in common is an increased frequency of the HLA-DR3 phenotype, demonstrating SSA(Ro) antibody activity and the typical annular, polycyclic, erythematous lesions of subacute cutaneous LE. The sicca symptoms of SS may develop long after the cutaneous lesions of LE have been present, or vice versa, as well as vasculitic, purpuric, and Sweet's syndrome-like lesions. The elderly, predominantly female patients are at enhanced risk for pulmonary and neurological disease, but glomerulonephritis occurs infrequently. We present an 81-year-old, SSA(Ro) antibody-positive and HLA-DR3-positive woman with SS/LE overlap syndrome, who had cutaneous LE for 30 years, developing sicca symptoms, vasculitic and Sweet's syndrome-like skin lesions only years after the LE symptoms. Although there is still some discussion as to whether phenotypical SS/LE overlap represents a distinct disease or is secondary SS in SLE or systemic SS with cutaneous involvement, the SS/LE overlap syndrome seems well enough delineated to be considered as a disease entity with separate implications for therapy and prognosis. Its position in the spectrum of anti-SSA(Ro) antibody- and HLA-DR3-positive diseases and its relationship to SS and to anti-SSA(Ro) antibody-positive LE are discussed.

Aged↗
PubMed1995

[Clinical double-blind trial of topical zinc sulfate for herpes labialis recidivans].

In a placebo controlled, double-blind clinical trial in patients with herpes labialis recidivans, zinc sulfate (CAS 7733-02-0) as gel (Virudermin Gel) proved to be significantly more effective than the gel alone. With zinc sulfate as gel, the symptoms were less marked and healing was faster. This simple preparation can be applied in cases of herpes labialis recidivans without any risk of side effects. Due to the antiseptic properties of zinc sulfate superinfections can be prevented.

Administration, Topical↗
PubMed1994

[Prepubertal hypertrichosis].

Hypertrichosis must be assessed in the light of the type of hair involved, the pattern of abnormal hair growth, associated abnormalities, age of onset, and family history including ethnic background. Associated diseases and the associated medication must be considered, as drug-induced hair growth is not uncommon. Although disorders of the hair usually have little medical significance and involve no interference with the general physical condition, they may be present in congenital syndromes or be associated with other abnormalities and metabolic disorders. The individual psychological impact of excessive hair growth also has a bearing on the problem with regard to its management. We describe in a 7-year-old girl and an 8-year-old boy a state of prepubertal hypertrichosis, characterized in otherwise normal children by a form of generalized excessive terminal hair growth which does not conform to the pattern of (androgen-mediated) hirsutism. The nosology of this form of excessive hair growth is discussed. The question whether it represents an atavistic trait is controverted.

Algorithms↗
PubMed1993

Common allergenic structures in hazelnut, rye grain, sesame seeds, kiwi, and poppy seeds.

Allergy to kiwi, poppy seeds, and/or sesame seeds often occurs in patients with a simultaneous sensitization to nuts and flour. Previously cross reactions have been verified by RAST inhibition. In this study the nature of this cross-reactivity is further characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), followed by immunoblotting to nitrocellulose. The degree of cross-reactivity among kiwi, sesame seeds, poppy seeds, hazelnuts, and rye grain was found to be very high in the patients studied. The existence of both cross-reacting and unique components was observed; however, the cross-reacting and unique components could be different for different patients.

Adolescent↗
PubMed1992

[Epidemiology of constitutional atopic neurodermatitis].

There are more and more reports of an increase in atopic diseases, and particularly atopic constitutional neurodermatitis. In this context, evidence is accumulating that atopic constitutional neurodermatitis exhibits a dominant prevalence, particularly in children. In addition to verified genetic disposition with impairment of IgE regulation, realization factors of greatly variant quality and quantity appear to be characteristically responsible for the phenotypic expression and determination of the course of the disease. In order to definitively assess the global situation, subtle longitudinal studies on representative numbers of the population are needed, with the primary objective of obtaining parameters for real preventative measures.

Adult↗
PubMed1991

[Borrelia infections from a dermatological viewpoint].

Erythema migrans (EM), Borrelia lymphocytoma (BL) and acrodermatitis chronica atrophicans (ACA) are the established dermatological manifestations of borrelia infection, a complex multiorganic disease. Analogous to syphilis Borrelia infection can be classified by three stages, at which stage I (localized infection) and II (disseminated infection) are manifestations of early infection and stage III (persistent infection) a symptom of late infection. At all stages skin manifestations can be present, the above mentioned as stage-marker as well as other non-specific polymorphous skin lesions which sometimes appear at stage II. Because of its frequent (60-80%) occurrence in all borrelia infections EM has a pathognomonic importance for borrelia infection. In diagnosis serology is currently the only practical laboratory aid. False negative and false positive results must be considered. Treatment of choice is ceftriaxone, penicillin G (or amoxycillin) or tetracycline. Prophylactic antibiotic therapy for tick bites is not recommended. Congenital borrelia infections seem to be unusual, but it is likely that they can occur and cause different adverse fetal outcome or abortion.

Acrodermatitis↗
PubMed1989

[The significance of dermatologic management in computer-assisted occupational dermatology consultation].

At our occupational outpatient clinic, 230 patients were treated for about 15 months. With the help of a standardized questionary, we registered all the data regarding the relevant substances the patients contacted during their work as well as their various jobs since they left school. The patients were repeatedly seen and trained in procedures of skin care and skin protection. If required, we took steps to find new jobs for them within their employing company; this was done in cooperation with the trade cooperative association according to the dermatological insurance consultanship. If these proceedings did not work out, the patient had to change his profession altogether. All data were computerized. As an example for this computer-based documentation we present the data of barbers.

Adult↗