Biomedical subjects

Alejandro Ruiz Lascano

Publications and source records attributed to Alejandro Ruiz Lascano.

9 recordsLinked to original sources

PubMed2005

[Acquired palmoplantar keratoderma with hypothyroidism].

We report the case of a 45 year-old male with palmoplantar hyperkeratosis. He had chronic thyroiditis with severe hypothyroidism. Skin lesions improved upon thyroid hormone replacement. Complete resolution of palmoplantar keratoderma was achieved after 7 months of therapy. The association of acquired palmoplantar keratoderma with hypothyroidism even though extremely unusual, should be considered in the differential diagnosis. It is a reversible condition.

Humans↗

PubMed2005

[Risk factors for basal cell carcinoma. Case-control study in Cordoba].

Basal cell carcinoma is undoubtedly a complex disease. Its etiology is still unclear and despite its frequency, there is a paucity of data on its risk factors. We assessed potential risk factors for basal cell carcinoma in a population from Córdoba (Argentina). This case-control study involved 88 newly diagnosed cases and 88 controls, matched by age and sex. The following risk factors were significant in the multivariate analysis: skin type I-II-III, high recreational sun exposure after 20 years of age, high sun exposure for beach holidays and actinic keratosis.

Adult↗

PubMed2004

Up-regulation of the chemokine CCL21 in the skin of subjects exposed to irritants.

BACKGROUND: Expression of murine CCL21 by dermal lymphatic endothelial cells (LEC) has been demonstrated to be one of the most important steps in Langerhans cell emigration from skin. Previously, our group and others have found that this chemokine is up-regulated in different human inflammatory skin diseases mediated by diverse specific immune responses. This study was carried out to investigate the involvement of CCL21 in human skin after challenge with irritant agents responsible for inducing Irritant Contact Dermatitis (ICD). RESULTS: Eleven normal individuals were challenged with different chemical or physical irritants. Two patients with Allergic Contact Dermatitis (ACD) were also challenged with the relevant antigen in order to have a positive control for CCL21 expression. Macroscopic as well as microscopic responses were evaluated. We observed typical ICD responses with mostly mononuclear cells in perivascular areas, but a predominance of polymorphonuclear cells away from the inflamed blood vessels and in the epidermis at 24 hours. Immunohistochemical studies showed up-regulation of CCL21 by lymphatic endothelial cells in all the biopsies taken from ICD and ACD lesions compared to normal skin. Kinetic study at 10, 48, 96 and 168 hours after contact with a classical irritant (sodium lauryl sulphate) showed that the expression of CCL21 was increased in lymphatic vessels at 10 hours, peaked at 48 hours, and then gradually declined. There was a strong correlation between CCL21 expression and the macroscopic response (r = 0.69; p = 0.0008), but not between CCL21 and the number of infiltrating cells in the lesions. CONCLUSIONS: These results provide new evidence for the role of CCL21 in inflammatory processes. Since the up-regulation of this chemokine was observed in ICD and ACD, it is tempting to speculate that this mechanism operates independently of the type of dermal insult, facilitating the emigration of CCR7+ cells.

Adult↗

PubMed2004

Secondary lymphoid tissue chemokine (CCL21) is upregulated in allergic contact dermatitis.

Chemokines are important players in the development of allergic contact dermatitis (ACD). The participation of secondary lymphoid tissue chemokine (CCL21) is essential in the induction of the disease due to its expression in lymphatic vessels and in secondary lymphoid organs. Since there is no information about its participation during the effector phase of ACD, we studied this chemokine in patients already diagnosed with ACD, who were challenged with the relevant positive and negative (control) antigens. All patients showed a specific antigen-induced immune response characterized by early expression of inflammatory markers in blood endothelial cells followed by dermal accumulation of mononuclear cells with an important increase in infiltration of CXCR3+ but not of CCR7+ cells. In situ hybridization and immunohistochemistry showed low levels of CCL21 in lymphatic vessels at 2 h, whereas they were significantly increased at 10 and 48 h in all positive patch tests. In contrast, very low expression of this chemokine was observed in skin biopsies from the control site at 48 h. In addition, Langerin+ cells, which were present in dermis from positive patch tests at 2 h, were diminished in number at 10 and 48 h, but a significant number of those cells was still present in dermal areas of the control site at 48 h. We demonstrate for the first time that CCL21, a constitutively expressed chemokine, is strongly upregulated in human lymphatic vessels during a Th1/Tc1 allergic inflammatory response. This can provide the signal required for CCR7+ cells to leave the skin through CCL21-positive lymphatic vessels.

Adult↗

PubMed2004

[Risk factors for cutaneous melanoma: case-control study in Córdoba, Argentina].

Over the past years, considerable effort has been directed toward the identification of risk factors associated with the increasing incidence of cutaneous melanoma in white populations worldwide. Limited data are available from Argentine populations concerning risk factors for malignant melanoma. A case-control study was performed in Cordoba to estimate the risk factors for cutaneous malignant melanoma. The study group comprised 65 patients and 195 controls, matched by age and sex. The following risk factors were significant in the univariate analysis: European grandparents, blonde and brown hair, fair skin tone, light colored and brown eyes, presence of freckles and melanocytic nevi, severe sunburns before the age of 18 years, recreational sun exposure, family history of malignant melanoma. In the multivariate analysis, European grandparents (OR 2.27, IC95% 1.08 to 3.46), fair skin (OR 4.99, IC95% 2.72 to 7.28), severe sunburns before the age of 18 (OR 6.47, IC95% 5.29 to 7.65), and family history of malignant melanoma (OR 1525, IC95% 1467 to 1584), remain as independent risk factors for malignant melanoma. The results of the current study are similar to those obtained in other populations.

Adolescent↗

PubMed2003

[Mucocutaneous lesions in patients with systemic lupus erythematosus].

The objective was to analyze the prevalence of mucocutaneous lesions in patients with systemic lupus erythematosus (SLE). During a 3-year period, we analyzed 77 patients with a diagnosis of SLE. The mucocutaneous lesions were classified into specific and non-specific. We defined skin type, sunlight exposure and photoprotection and correlated these lesions with serology and disease activity. Acute specific lesions were found in 67.5% of the patients, subacute lupus in 6.5% and chronic lesions in 26.0%. The most prevalent non-specific lesions were alopecia (59.7%), photosensitivity (57.1%), Raynaud's syndrome (46.7%), oral ulcerations (15.6%) and livedo reticularis (11.7%). Skin type 3 (35%) and exposure to mild ultraviolet radiation (74%) were seen in the majority of the patients. Appropriate sunlight protection was only used by 47% of the patients. When dermatological lesions and serology were compared, we found a significant association between malar rash, photosensitivity, livedo reticularis and alopecia with the presence of anti-Ro and Raynaud's phenomenon in patients with positive anti-Sm. The presence of malar rash, photosensitivity, Raynaud's phenomenon, diffuse alopecia and livedo reticularis was more frequent among patients with active disease. The prevalence of mucocutaneous manifestation in our population was slightly higher than data reported in other series. The presence of malar rash, diffuse alopecia, photosensitivity and livedo reticularis significantly related with the presence of anti-Ro and Raynaud's phenomenon with anti-Sm. All these lesions were more frequently seen in patients with active disease.

Adolescent↗

PubMed2002

Early inflammatory markers in elicitation of allergic contact dermatitis.

BACKGROUND: Allergic Contact Dermatitis (ACD) is regarded as a T-cell-mediated delayed-type hypersensitivity reaction. We studied the kinetics of the expression of CS-1 fibronectin, thymus and activation-regulated chemokine (CCL17/ TARC) and different chemokine receptors (CR) in skin biopsies from individuals suffering from back problems, with the antigen responsible of their contact dermatitis and an irrelevant antigen. METHODS: Samples were taken at 2, 10, and 48 hours for histological and immunohistochemical studies using monoclonal antibodies against human CS-1 fibronectin, CCL17, CD3, CD68, CD49d, CXCR3, CCR5, and CCR3. RESULTS: At positive antigen stimulated sites there was an early expression of CS-1 fibronectin (2 hours), followed by CCL17 and a later accumulation of alplha4/beta1+ (CD49d), CD3+, CD68+, CXCR3+ and CCR5+ mononuclear cells. At 48 hours, approximately 59 % of infiltrating cells were CXCR3+, 42% CCR5+, and only 14 % CCR3+. CONCLUSIONS: These results showed for the first time a very early expression of CS-1 fibronectin which preceded production of CCL17 in blood endothelial cells (BCEs) from patients' skin with ACD. The role of these molecules in recruitment of monocytes and effector T cells in ACD is discussed.

Adult↗

PubMed2002

[Cytomegalovirus cellulitis].

Cutaneous lesions in CMV infection are rare, often a late manifestation of systemic infection, and usually herald a fatal course. A 70 year-old woman received a kidney transplantation one month before consulting and immunosuppressive therapy that included cyclosporine A and methylprednisone. She complained of fever, local pain in her right leg, and an erythematous and swelling plaque. She was treated with intravenous antibiotics without improvement. A skin biopsy was performed and the tissue obtained was sent for bacterial and fungal cultures as well as for histological examination. Cultures were negative. The biopsy showed CMV cytopathic changes. Immunoperoxidase staining was positive for CMV and polymerase chain reaction (PCR) testing revealed CMV DNA. She was treated with ganciclovir with resolution of the lesion. CMV cellulitis is a rare cutaneous manifestation which has not been previously reported.

Aged↗

PubMed2002

[Extranodal NK/T cell lymphoma of the nasal type].

The vast majority of lymphoma occurring in the testis are diffuse large B-cell Lymphoma. We report on a case of natural killer/T cell lymphoma in a forty four year old male, with bilateral testicular and cutaneous involvement with a highly aggressive course. The tumor cells were positive for both CD56 and Epstein Barr Virus, encoded EBER molecules, and showed focal angiocentric growth thus fullfilling the criteria for NK/T cell lymphoma of nasal type. Dermatopathologists and uropathologists should be aware of this rare entity which may only be diagnosed after extensive inmunohistochemical studies.

Adult↗