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S Chimenti

Publications and source records attributed to S Chimenti.

At least 37 records · Page 2Linked to original sources
PubMed2001

The use of high-dose immunoglobulin in the treatment of pyoderma gangrenosum.

BACKGROUND: Immunosuppressive medications such as corticosteroids and cyclosporin are the most commonly employed therapies in pyoderma gangrenosum. We describe a patient with multiple ulcers of pyoderma gangrenosum on the lower extremities in whom immunosuppressive therapy caused serious side effects and had to be discontinued but who was subsequently treated successfully with high dose intravenous immunoglobulin (IVIG). METHODS: IVIG was given intravenously at a dose of 400 mg/kg per day for 5 consecutive days. After 1 week there was an arrest in the progression of the ulcers and a marked reduction in pain. Two weeks later clinical improvement of the ulcers was observed. Subsequently, IVIG was given at a dose of 1 g/kg per day for 2 consecutive days. RESULTS: The treatment induced a dramatic clinical improvement of one ulcer and healing of the others. Side effects were minimal and well tolerated, and consisted of chills and a slight fever, which resolved with the administration of acetaminophen. CONCLUSION: We feel that IVIG can be used in patients with pyoderma gangrenosum in whom conventional therapies are ineffective or produce serious side effects.

Aged↗
PubMed2001

Differentiation between pigmented Spitz naevus and melanoma by digital dermoscopy and stepwise logistic discriminant analysis.

Epiluminescence light microscopy (ELM) has proven useful in the diagnosis of pigmented skin lesions (PSLs). However, in some cases this technique does not sufficiently increase the diagnostic accuracy in distinguishing pigmented Spitz naevi (PSNs) from melanoma. With the aim of obviating these problems of qualitative interpretation, methods based on the mathematical analysis of PSLs, such as digital dermoscopy analysis (DDA), have recently been developed. In the present study we used a digital dermoscope (DBDermo-MIPS, Dell'Eva-Burroni) to analyse PSNs and melanomas with similar clinical and dermoscopic features for any correlation between variables and to determine its discriminating power with respect to histological diagnosis. The 100 lesions underwent histological examination by three experienced dermatopathologists and were identified as PSNs (43) or melanomas (57). Thirty-six parameters were identified as possible discriminating variables and were grouped in four categories: geometry, colour, texture, and islands of colour. Statistical analysis was used to identify the variables with the highest discriminating power. Stepwise discriminant analysis selected only four variables: entropy, minimum diameter, red lesion value and peripheral dark (the means of these variables were higher in melanomas than in PSNs). Thus the combined use of digital dermoscopy and stepwise logistic discriminant analysis made it possible to single out the best objective variables for distinguishing PSN and melanoma.

Dermatology↗
PubMed2001

Transplanted adult bone marrow cells repair myocardial infarcts in mice.

Occlusion of the anterior descending left coronary artery leads to ischemia, infarction, and loss of function in the left ventricle. We have studied the repair of infarcted myocardium in mice using highly enriched stem/progenitor cells from adult bone marrow. The left coronary artery was ligated and 5 hours later Lin- c-kit+ bone marrow cells obtained from transgenic male mice expressing enhanced green fluorescent protein (EGFP) were injected into the healthy myocardium adjacent to the site of the infarct. After 9 days the damaged hearts were examined for regenerating myocardium. A band of new myocardium was observed in 12 surviving mice. The developing myocytes were small and resembled fetal and neonatal myocytes. They were positive for EGFP, Y chromosome, and several myocyte-specific proteins including cardiac myosin, and the transcription factors GATA-4, MEF2, and Csx/Nkx2.5. The cells were also positive for connexin 43, a gap junction/intercalated disc component indicating the onset of intercellular communication. Myocyte proliferation was demonstrated by incorporation of BrdU into the DNA of dividing cells and by the presence of the cell cycle-associated protein K167 in their nuclei. Neo-vascularization was also observed in regenerating myocardium. Endothelial and smooth muscle cells in developing capillaries and small arterioles were EGFP-positive. These cells were positive for Factor VIII and alpha smooth muscle actin, respectively. No myocardial regeneration was observed in damaged hearts transplanted with Lin- c-kit- bone marrow cells, which lack bone marrow-regenerating activity. Functional competence of the repaired left ventricle was improved for several hemodynamic parameters. These in vivo findings demonstrate the capacity of highly enriched Lin- c-kit+ adult bone marrow cells to acutely regenerate functional myocardium within an infarcted region.

Actins↗
PubMed2001

Superficial black network: an additional dermoscopic clue for the diagnosis of pigmented spindle and/or epithelioid cell nevus.

Dermoscopy is a valuable method for improving the diagnostic accuracy of pigmented skin lesions. Specific dermoscopic criteria have been described for differentiating pigmented spindle and/or epithelioid cell nevi (SECN; Spitz nevi and Reed nevi) from cutaneous melanomas. In the present study, we report an additional dermoscopic feature of SECN, namely a distinctive type of pigment network, described as superficial black network, which was observed in 10.5% of SECN. Histopathologically, this network corresponds to focal areas of pigmented parakeratosis, producing a black reticulated appearance on the horizontal plane.

Adolescent↗
PubMed2001

IGF-1 overexpression inhibits the development of diabetic cardiomyopathy and angiotensin II-mediated oxidative stress.

Stimulation of the local renin-angiotensin system and apoptosis characterize the diabetic heart. Because IGF-1 reduces angiotensin (Ang) II and apoptosis, we tested whether streptozotocin-induced diabetic cardiomyopathy was attenuated in IGF-1 transgenic mice (TGM). Diabetes progressively depressed ventricular performance in wild-type mice (WTM) but had no hemodynamic effect on TGM. Myocyte apoptosis measured at 7 and 30 days after the onset of diabetes was twofold higher in WTM than in TGM. Myocyte necrosis was apparent only at 30 days and was more severe in WTM. Diabetic nontransgenic mice lost 24% of their ventricular myocytes and showed a 28% myocyte hypertrophy; both phenomena were prevented by IGF-1. In diabetic WTM, p53 was increased in myocytes, and this activation of p53 was characterized by upregulation of Bax, angiotensinogen, Ang type 1 (AT(1)) receptors, and Ang II. IGF-1 overexpression decreased these biochemical responses. In vivo accumulation of the reactive O(2) product nitrotyrosine and the in vitro formation of H(2)O(2)-(.)OH in myocytes were higher in diabetic WTM than TGM. Apoptosis in vitro was detected in myocytes exhibiting high H(2)O(2)-(.)OH fluorescence, and apoptosis in vivo was linked to the presence of nitrotyrosine. H(2)O(2)-(.)OH generation and myocyte apoptosis in vitro were inhibited by the AT(1) blocker losartan and the O(2) scavenger TIRON: In conclusion, IGF-1 interferes with the development of diabetic myopathy by attenuating p53 function and Ang II production and thus AT(1) activation. This latter event might be responsible for the decrease in oxidative stress and myocyte death by IGF-1.

Angiotensin II↗
PubMed2000

Dermoscopic features of cutaneous local recurrent melanoma.

We describe for the first time the dermoscopic features of cutaneous recurrent melanoma including a globular pattern and a diffuse nonhomogeneous pigmentation. These findings greatly differ from those observed in primary cutaneous melanoma and should be considered in the dermoscopic differential diagnosis of pigmented skin lesions.

Adult↗
PubMed2000

Central white scarlike patch: a dermatoscopic clue for the diagnosis of dermatofibroma.

In this study, dermatoscopic examination of 24 dermatofibromas was performed to evaluate specific dermoscopic criteria. A central white scarlike patch was appreciable in 22 of 24 lesions, whereas 20 of 24 dermatofibromas exhibited a delicate pigment network at the periphery. This stereotypical dermatoscopic finding allowed the diagnosis of dermatofibroma in most instances. (J Am Acad Dermatol 2000;43:1123-5.).

Adult↗
PubMed2000

Teledermoscopy--results of a multicentre study on 43 pigmented skin lesions.

We performed a multicentre study to evaluate the agreement between the direct clinical diagnosis and the telediagnosis of 43 cutaneous pigmented lesions. Digital clinical and dermoscopic images of the 43 pigmented skin lesions (11 melanomas, 23 melanocytic naevi, three basal cell carcinomas, three lentigines, two seborrhoeic keratoses and one angiokeratoma) were sent by email to 11 colleagues (six dermatologists, two residents in dermatology, one oncologist, one specialist in internal medicine and one general practitioner) in 10 centres. These 11 colleagues had different degrees of experience in dermoscopy. With histopathology as the gold standard, an average of 85% of the telediagnoses were correct, with results varying from 77% to 95%, whereas face-to-face diagnosis by an expert dermatologist was correct in 91% of cases. The kappa value for all participants ranged from 0.35 to 0.87. The results confirm that teledermoscopy can be a reliable technique for the diagnosis of pigmented skin lesions but one that will depend on the expertise of the observer.

Adolescent↗
PubMed1999

Face-to-face diagnosis vs telediagnosis of pigmented skin tumors: a teledermoscopic study.

BACKGROUND: Teledermoscopy uses telecommunication technologies to transfer images of pigmented skin lesions, including clinical and anamnestic data, via e-mail to specialized centers for teleconsultation. DESIGN: Sixty-six pigmented skin lesions examined on a face-to-face basis in a skin lesion clinic in L'Aquila, Italy, were sent via e-mail on a standard-resolution color monitor for consultation at a university dermatology department in Graz, Austria. INTERVENTION: Digital photographs of the clinical and dermoscopic images of all pigmented tumors were taken with a stereomicroscope connected to a high-resolution video camera in Truevision advanced graphic array (Targa) format file and converted successively into a Joint Photographic Expert Group (PEG) format file. All lesions were excised surgically and diagnosed histopathologically. MAIN OUTCOME MEASURE: Diagnostic concordance between face-to-face diagnosis and telediagnosis. RESULTS: The diagnostic concordance was 60 (91%) of 66 cases. The number of correct telediagnoses was lower, but the difference was not statistically significant (Wilcoxon test, P = .10). The accuracy of the telediagnoses was not related to the quality of the images, but highly depended on the level of diagnostic difficulty of a given pigmented skin tumor (Spearman correlation, P= .01). CONCLUSION: Teleconsultation of clinical and dermoscopic images of skin tumors via e-mail provides a similar degree of diagnostic accuracy as face-to-face diagnosis.

Adolescent↗
PubMed1999

Reduced expression of CDKN2a/P16INK4a in mycosis fungoides.

Alterations in the CDKN2a gene have been demonstrated in a wide range of human tumors including hematopoietic malignancies. To verify whether altered CDKN2a expression is involved in the pathogenesis of mycosis fungoides (MF), we examined mRNA expression in 20 patients with MF by RT-PCR and dot blot hybridization. CDKN2a mRNA expression was undetectable in 5 of the 20 patients (25%), intermediate in 13 (65%) and high in 2 (10%). Immunohistochemical studies, which were performed in ten patients, revealed that in the four patients showing no mRNA, p16INK4a was expressed in <1% of neoplastic lymphocytes whereas in the four patients with an intermediate mRNA level, specific nuclear staining was present in 1-25% of tumor cells. In the two patients with high levels of CDKN2a mRNA, >25% of neoplastic lymphocytes stained positively. No direct correlation between clinicopathological and molecular findings was evident in our patients. DNA mutational analysis revealed no alterations in a total of six patients examined. Our results indicate that the lack of CDKN2a expression, as found in 25% of the patients, may have a pathogenetic role in MF even though the absence of CDKN2a mRNA was not associated with point mutations or minor gene deletions.

Adolescent↗
PubMed1999

The use of chemical peelings in the treatment of different cutaneous hyperpigmentations.

BACKGROUND: Several chemical agents including hydroquinone, retinoic acid, and azelaic acid are currently used in the treatment of cutaneous hyperpigmentations. Recently chemical peelings with kojic acid, glycolic acid, and trichloroacetic acid, either alone or in combination, have been introduced for treatment of hyperpigmentations. OBJECTIVE: The purpose of our study was to evaluate the efficacy of trichloroacetic acid as well as glycolic acid associated with kojic acid in the treatment of cutaneous hyperpigmentations. METHODS: Twenty patients with diffuse melasma were treated with a solution composed of 50% glycolic acid and 10% kojic acid whereas 20 patients with localized hyperpigmentations (lentigo) were treated with 15%-25% trichloroacetic acid. RESULTS: Complete regression of diffuse melasma was observed in 6 of 20 patients (30%), a partial regression in 12 of 20 patients (60%), and no regression in 2 of 20 patients (10%) treated with 50% glycolic acid and 10% kojic acid. Complete regression of localized hyperpigmentations was observed in 8 of 20 patients (40%), a partial regression in 10 of 20 patients (50%), and no regression in 2 of 20 patients (10%) treated with 15-25% trichloroacetic acid. CONCLUSIONS: Based on our findings, both peelings can be considered effective in the treatment of cutaneous hyperpigmentations.

Adult↗
PubMed1999

Cutaneous involvement in lymphoblastic lymphoma.

Lymphoblastic leukemia/lymphoma (LBL) is a malignant neoplasm of precursor lymphocytes of B- or T-cell phenotype. Involvement of the skin is relatively uncommon. We examined retrospectively the clinicopathologic, immunophenotypic, and molecular genetic features of six patients with cutaneous involvement of LBL (B-LBL=5; T-LBL=1). Patients presented clinically with solitary, large tumors located on the head (3 cases) or the back (1 case), or with generalized tumors (2 cases). Ulceration was uncommon. In two patients the onset of skin lesions was concomitant to the diagnosis of lymphoblastic leukemia. Histopathologic examination showed in all cases a dense, diffuse, monomorphous infiltrate located in the entire dennis and subcutaneous fat. A typical "starry sky" pattern was observed in the majority of the lesions. In some areas neoplastic cells were aligned in a "mosaic-like" fashion. Cytomorphologically, medium sized lymphoid cells with round or convoluted nuclei, inconspicuous nucleoli and scant cytoplasm predominated. There were no significant differences in the histopathologic features of skin lesions in T- and B-LBL. In B-LBL, CD79a was more useful than CD20 in determining the phenotype of neoplastic cells (4/5 cases positive for CD79a as compared to 2/5 cases positive for CD20). TdT, CD10 and CD43 were positive in 4 cases, CD34 in 2. The case of T-LBL revealed positivity for CD1a, CD3, CD43 and TdT, and negativity for CD34 and for B-cell markers. All neoplasms were positive for CD99 and bcl-2, and showed a high proliferation rate. Molecular genetic analysis of J(H) and T-cell receptor (TCR) genes performed using a polymerase chain reaction technique revealed a monoclonal rearrangement of J(H) genes in all five B-LBLs. One of these cases showed also a concomitant TCR-gamma gene rearrangement. A monoclonal rearrangement of the TCR-gamma gene was detected in the case of T-LBL. Our study shows that skin lesions of LBL present characteristic clinicopathologic and molecular features allowing the differentiation from other cutaneous lymphomas, even in cases without clinical history of previous precursor lymphoblastic leukemia/lymphoma.

Adult↗
PubMed1998

Peripheral nervous system involvement in a patient with large T-cell lymphoma arising from a pre-existing mycosis fungoides.

A 29-year-old man was examined for disseminated erythematous scaling patches and plaques and reddish, partially ulcerated nodules. Histological examination showed a dense, diffuse, epidermotropic infiltrate located in the entire dermis to the subcutaneous tissue, composed mainly of large pleomorphic T lymphocytes. Immunohistochemistry revealed positivity of neoplastic cells for T-cell-associated markers, negativity for CD30 antigen and for B-cell markers. Polymerase chain reaction analysis detected a clonal amplification of T-cell receptor gamma. Based on clinicopathological and molecular findings, the diagnosis of large T-cell lymphoma (LCL) arising from a pre-existing mycosis fungoides was made. Seven months after primary diagnosis, meningeal and peripheral nervous system involvement developed with no other evidence of systemic disease. Despite chemotherapy and radiation therapy, the patient died 3 months after the diagnosis of nervous system involvement. In patients with cutaneous LCL, mild neurological symptoms may precede the complete diagnostic picture by some weeks. A rapid and fatal progression characterizes the clinical course of the disease.

Adult↗