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J Tousignant

Publications and source records attributed to J Tousignant.

27 records · Page 2Linked to original sources
PubMed1990

[Immunohistochemical characteristics of malignant melanoma. A study of 40 cases and review of the literature].

An immunohistochemical study of 40 primary and secondary malignant melanomas in 27 patients, with routinely-used monoclonal antibodies, demonstrated the antigenic pattern exhibited by these tumors, as well as the frequency of aberrant positivities for epithelial cell markers. The following results were found: 95% of melanomas stained positively for S100 protein and vimentin, which is the characteristic immunohistochemical pattern in melanomas. In most cases, the primary tumor and its metastases in a given patient had the same antigenic phenotype. As for epithelial markers, 10% of melanomas stained positively for KL1 and 27.5% for EMA. Despite this relatively high frequency of KL1 and EMA positivities, in practice, simultaneous positivity for S100 protein and vimentin, confronted with the patient's history and with histologic features, firmly establishes the diagnosis of malignant melanoma in virtually all cases.

Adult↗
PubMed1990

[Post-varicella anetoderma. 3 cases].

We report three cases of typical macular atrophy which appeared during, or was noticed shortly after varicella. The three patients were children. These cases were particular in that anetoderma lesions occurred independently of the scarring varicella lesions and followed a prolonged course of their own afterwards. We were unable to classify these cases in the primary or secondary type of macular atrophy. The various dermatoses associated with macular atrophy and the numerous physiopathological hypotheses put forward concerning this entity are enumerated.

Atrophy↗
PubMed1990

[A case of malignant melanoma expressing epithelial cell markers in immunohistochemistry using paraffin sections].

Recently, applications of immunohistochemical techniques for the cytoplasmic localization of intermediate filaments has produced advances in tumor diagnosis and characterization. We report a 58-year-old white male with a clinically and histologically typical metastatic malignant melanoma. This case was peculiar because the same neoplastic cells stained for both S-100 protein and keratin on paraffin embedded tissue. These facts illustrate how cautiously we must interpret the positivity of immunohistochemical technics. We thus insist on the importance of the clinical and basic histologic data for the diagnosis, in order to avoid errors.

Biomarkers, Tumor↗
PubMed1987

Treatment of cutaneous T-cell lymphoma with the arotinoid Ro 13-6298.

Mycosis fungoides is a neoplasia immunologically defined as a cutaneous T cell lymphoma. It is an uncommon, chronic, and usually fatal disease that runs a progressive multistaged course. The present study describes a case of mycosis fungoides, limited to the skin, which was successfully controlled with the arotinoid Ro 13-6298. Review of the role of retinoids in dermatology and oncology is presented with a special emphasis on the arotinoid.

Antineoplastic Agents↗
PubMedDate not supplied

Recombinant human platelet-derived growth factor-BB (becaplermin) for healing chronic lower extremity diabetic ulcers: an open-label clinical evaluation of efficacy.

Topically applied recombinant human platelet-derived growth factor-BB (becaplermin) is a new pharmacologically active therapy for chronic, neuropathic, lower extremity diabetic ulcers. In previous studies, becaplermin gel was administered once daily but dressings were changed twice daily. In the present study of 134 patients with diabetes mellitus and full thickness lower extremity ulcers, dressings were changed only once per day, simplifying the treatment regimen. Efficacy criteria included the percentage of patients achieving complete healing within the 20-week treatment period, the time to achieve complete healing, the rate of ulcer recurrence during the 6-month period following healing, and treatment compliance. Complete healing of ulcers was achieved in 57. 5% of patients, with a mean time to closure of 63 days and a recurrence rate of 21% at 6 months. Of the potential factors affecting ulcer healing, only drug compliance (p < 0.001), dressing compliance (p < 0.01), the presence of infection (p < 0.01), baseline ulcer area (p < 0.05), and baseline total wound evaluation score (p < 0.05) were significantly associated with healing. Results of this study further confirm the efficacy and safety of becaplermin gel for the treatment of lower extremity diabetic ulcers.

Becaplermin↗
PubMedDate not supplied

Development of noninvasive and quantitative methodologies for the assessment of chronic ulcers and scars in humans.

Chronic ulcers are a significant and common cause of morbidity and mortality worldwide. They disrupt the epidermis and dermis, resulting in a loss of barrier function. Keloids and hypertrophic scars (benign cutaneous tumors) represent an abnormal healing response. These fibroproliferative disorders are characterized by an overabundance of collagen and accumulation of extracellular matrix due to an imbalance between synthesis and degradation, culminating in excessive scarring. The objectives of this study were to evaluate and compare noninvasive biophysical methods for the measurement of outstanding quantitative parameters of scars and chronic ulcers, and to establish correlations between the parameters measured and the results of conventional subjective clinical evaluations. The development of new technologies, based on ultrasonography and laser Doppler, makes possible new dermatological evaluation methods. Fifteen patients (6 females and 9 males) with 15 chronic ulcers (4 diabetic ulcers, 10 venous ulcers and 1 pressure ulcer) and 30 patients (19 females and 11 males) with 30 scars (25 hypertrophic and 5 keloids) were included in this study. Clinical evaluation was performed by a dermatologist, an aesthetic surgeon and an endocrinologist. Biophysical measurements were used to assess local blood flow by laser Doppler flowmetry (Moor DRT4), thickness and echogenicity by high frequency ultrasonography (20 MHz, Dermascan C) and ulcer linear dimensions by image analysis. Our results show that blood flow within the ulcers and scars was higher than within normal skin. Also, skin thickness of chronic ulcers was decreased when compared to normal skin; the thickness of hypertrophic scars, but not of keloids, was increased in comparison to normal skin, and presented the possibility of measuring wound and scar surfaces with precision. In summary, this pilot study established the feasibility of measuring various biophysical parameters and adapted their potential utility to research on wounds.

Adult↗