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Biomedical subjects

R J Barr

Publications and source records attributed to R J Barr.

At least 91 records · Page 5Linked to original sources
PubMed1987

Hypomelanosis associated with a colonic abnormality. A possible result of defective development of the neural crest.

A neonate born of black parents displayed a congenital, dramatic deficiency of most of his normal pigmentation. This was accompanied by a markedly dilated colon and various other defects. Light- and electron-microscopic examination revealed a deficiency in melanin content in the hypopigmented skin as compared to the normally pigmented areas. No other defects were noted. The possibility exists that a single aberration in neural crest development, a neurocristopathy, might be responsible for our patient's multiple congenital defects. Similar conditions in veterinary medicine and human disease are reviewed and compared to this case.

Abnormalities, Multiple↗
PubMed1986

Efficacy of doxepin in the treatment of chronic idiopathic urticaria.

Doxepin hydrochloride, a tricyclic antidepressant, was evaluated in a double-blind, placebo-controlled crossover trial for the treatment of chronic idiopathic urticaria in 16 adults. Efficacy was evaluated by symptom scores, concomitant antihistamine use, and suppression of histamine- and codeine-induced wheal response. Doxepin-treated subjects experienced fewer lesions (p less than 0.001), less waking hours with lesions (p less than 0.01), lesser degree of itch and/or discomfort (p less than 0.001), and less swelling or angioedema (p less than 0.001) as compared to placebo-treated subjects. Doxepin-treated subjects required less daily concomitant antihistamine use (mean 0.13 tablets versus 1.48 tablets, p less than 0.05). Doxepin also significantly suppressed histamine- and codeine-induced cutaneous wheal response as compared to placebo. Lethargy was commonly observed but diminished with continued use. Dry mouth and constipation were also commonly observed. We conclude that doxepin is an effective agent for the treatment of chronic idiopathic urticaria.

Chlorpheniramine↗
PubMed1986

Cutaneous keratocysts of nevoid basal cell carcinoma syndrome.

Four cysts were removed from two unrelated patients with nevoid basal cell carcinoma syndrome. Multiple sections from each cyst were studied. Two cysts showed histologic features similar to keratocysts that occur in the jaws of patients with this syndrome. The cysts were lined by a festooned epithelium consisting of two to five layers of squamous cells that formed keratin without the presence of a granular cell layer. One cyst contained some lanugo hair and a small bud of follicular epithelium. This cyst was therefore similar to cutaneous steatocysts but did not have an identifiable sebaceous component. The second cyst was devoid of hair and adnexal structures and was indistinguishable from a jaw keratocyst. Two other cysts were typical epidermoid (infundibular) cysts. Although speculative, it is likely that some cutaneous cysts in patients with nevoid basal cell carcinoma syndrome are identical to jaw keratocysts and may be another cutaneous marker for this disease complex.

Adult↗
PubMed1986

Prolonged viability of human skin xenografts in rats by cyclosporine.

The immunosuppressant cyclosporine (CSA) has shown usefulness in both animal and human transplantation. The present study investigated the effect of CSA in human to rat skin xenografts. Recipient rats received either a fresh split-thickness (0.020 in.) or full-thickness graft obtained from plastic surgery, or frozen cadaver skin. The graft bed of recipient Lewis rats was prepared by full-thickness excision. Animals were maintained on CSA 25 mg/kg/day X 50 days, followed by 12.5 mg/kg 2 X/week. Control animals received an equivalent volume of vehicle. All animals receiving split-thickness grafts and treated with CSA maintained their grafts significantly longer (up to 255 days) than controls. The 2 CSA-treated full-thickness grafts and the 10 vehicle-treated controls showed clinical and microscopic signs of rejection at a mean of 6.4 days. Histologic examination of successful grafts showed areas of viable epidermis with a negligible inflammatory infiltrate. There was some loss of normal polarity and occasional apoptotic pigmented basal cells. The dermis revealed moderate fibrosis, probably secondary to the surgical procedure. Graft viability was confirmed by autoradiography. Immunohistochemical staining for S-100 protein revealed morphologic alteration of suprabasilar dendritic (Langerhans-indeterminate) cells, as well as their existence in xenografts at 12 weeks posttransplantation. Toxicities reflected by weight loss and blood chemistries were felt to be dose-dependent. This in vivo model may provide a means for testing percutaneous drug penetration and pharmacokinetics in human skin, and for observing the immune component of explanted cutaneous neoplasms and dermatoses.

Animals↗
PubMed1986

Non-polarizable collagen in dermatofibrosarcoma protuberans: a useful diagnostic aid.

The stroma in dermatofibrosarcoma protuberans (DFSP) stains with trichrome, but is not polarizable (birefringent, doubly refractile). The usefulness of polarizing neoplastic stroma as a diagnostic aid in distinguishing DFSP from dermatofibroma and fibromatosis was evaluated. Forty cases of dermatofibroma of all types, 12 cases of dermal fibromatosis, and 15 cases of DFSP were examined. None of DFSPs contained polarizable collagen, whereas 11 of the 12 (92%) fibromatoses and 35 of the 40 (88%) dermatofibromas did. Of the 5 dermatofibromas that did not polarize, all were composed primarily of round to polyhedral histiocytic cells, including foam cells, frequently surrounding small obliterated capillaries. Although not pathognomonic, the presence of nonpolarizable collagen appears to be an additional histological marker useful in differentiating DFSP from dermatofibroma and fibromatosis.

Collagen↗
PubMed1986

Giant cell fibroblastoma: an immunohistochemical study.

Giant cell fibroblastoma is a rare, benign soft tissue tumor occurring in childhood. A 34-year-old woman presented with a giant cell fibroblastoma involving the chest wall. Histologic features include an infiltrating spindle-cell tumor involving the dermis and subcutaneous fat containing characteristic sinusoidal spaces rimmed by spindle cells and multinucleate giant cells. Immunohistochemical studies support a fibrohistiocytic differentiation.

Adult↗
PubMed1986

Loss of epidermal Langerhans' cells and endothelial cell HLA-DR antigens in the skin in progressive systemic sclerosis.

Skin biopsies from the volar aspect of the forearm were studied in 26 patients with progressive systemic sclerosis (PSS) (16 diffuse, 10 CREST) and 4 controls using monoclonal antibodies against Langerhans' cells, T lymphocytes, macrophages, B lymphocytes, NK/K cells and HLA-DR antigen(s). Langerhans' cells were reduced or absent (anti-T6, anti-HLA-DR) in 19 of 20 clinically involved and in all 6 uninvolved PSS skin biopsies. Electron microscopic studies of 3 PSS patients indicated a reduction in the number of Langerhans' cells, with normal morphology of the remaining. HLA-DR antigen(s) on dermal endothelial cells were absent or reduced in 8 of 20 involved and 5 of 6 uninvolved PSS skin biopsies, but were present on the surface of dermal mononuclear cells presumably representing activated T lymphocytes. Increased numbers of dermal macrophages were found in 19% of PSS biopsies compared with controls. Absence of Langerhans' cells appears to represent the most widespread immunopathological feature of PSS. It is also associated with absent endothelial HLA DR surface antigens and activated T lymphocytes within the dermis.

Biopsy↗
PubMed1986

Dermatologic applications of cyclosporine.

It is evident that cyclosporine A is a potent immunosuppressive agent and may become immensely valuable in the treatment of cutaneous disease. The extent of its application and efficacy is speculative, as neither the pathogenesis of many of the diseases, nor the mechanism of action of cyclosporine is fully understood. Well-designed clinical and laboratory studies are necessary to delineate its therapeutic value in a particular disorder. It must be emphasized that the systemic use of the drug is associated with several serious side effects, including nephrotoxicity and lymphoproliferative disease. Local topical application may reduce these concerns, and make treatment of benign diseases a possibility. Therefore, until these well-designed prospective studies are performed, cyclosporine's use should be limited and closely monitored.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Diffuse lipomatosis and tuberous sclerosis.

Diffuse lipomatosis, a classic example of an infiltrating fatty tumor, is a rare entity characterized by infiltration of adult-type adipose tissue into skin, subcutaneous tissue, and muscle. It usually involves a large portion of an extremity or the trunk. Some cases are associated with distant lipomas or angiomas, or hypertrophy of subjacent bone. The association of diffuse lipomatosis with tuberous sclerosis is reported.

Adolescent↗
PubMed1985

Sclerosing sweat duct (syringomatous) carcinoma.

This report describes 20 sclerosing adnexal carcinomas of the skin that recapitulate the sweat duct and share certain microscopic features with benign syringoma. Clinically, the neoplasms were slow-growing, indurated nodules or plaques. Sixteen were located on the face, including five on the upper lip. Three were situated in the axilla, and one involved the buttock. Twelve of the tumors (group 1) were composed primarily of cords and nests of whorled squamous cells with clear cell change and variable keratinization. Lumens consistent with ductal differentiation were few and isolated in some of these lesions, but others had more numerous and complex ducts. The remaining eight neoplasms (group 2) contained large numbers of small, uniform ducts, and exhibited little keratinization. Each neoplasm in the series infiltrated subcutaneous tissue or deeper tissues and was accompanied by sclerotic, fibrous stroma. Sixteen of the lesions (80%) exhibited perineural growth. One tumor involved an underlying lymph node, probably by direct extension. Cytologic atypicality was mild or lacking, and mitotic figures were sparse. Seven of 15 tumors (47%) with follow-up recurred, in some instances many years after primary excision. Tumor-free margins in the initial excision specimen appeared to be a favorable prognostic factor. The most aggressive lesion in the series showed increased cytologic atypicality in recurrences.

Adult↗
PubMed1985

Verrucous hemangioma.

Two patients with verrucous hemangioma, a congenital vascular malformation, were seen. The typical lesion is a unilateral group of hyperkeratotic papules and nodules on a lower extremity. Unlike the more common capillary or cavernous hemangiomas, verrucous hemangiomas tend to enlarge and spread with time, and to recur after excision.

Adolescent↗
PubMed1985

Paraffinomas of the scalp.

Four cases of scalp paraffinoma were seen in our clinics within the past year. This unusual condition results from intradermal injection of substances containing paraffin. The presence of paraffin in excised tissue was confirmed by thin-layer chromatography and infrared absorption spectrophotometry. Our patients received their treatments 35 to 42 years ago after responding to radio or newspaper advertisements that promised a cure for baldness. Two patients were initially observed with severe scalp inflammation and two were completely asymptomatic other than having lumpy scalps. Although these cases were readily diagnosed by history, eliminating other possibilities was greatly aided by use of xeroradiography, obviating the need for biopsy in asymptomatic cases.

Aged↗
PubMed1984

Cutaneous cytology.

Cutaneous cytology is the study of scrapings or smears obtained from lesions of the skin. Although not commonly employed, cutaneous cytology has become a useful tool for clinicians due to the development of simplified procedures and staining technics. This review describes basic principles and illustrates the usefulness of cutaneous cytology in studying selected vesiculobullous and pustular dermatoses, neoplasms, superficial fungal infections, and miscellaneous applicable disorders. Sophisticated diagnostic tumor cytology and new methodology, such as immunohistochemistry and intricate morphometric analyses, are also briefly discussed.

Carcinoma in Situ↗
PubMed1984

Fixed-tissue binding of fluorescein-conjugated concanavalin A to malignant melanomas versus nevi.

Concanavalin A (con A) is a plant-derived lectin that has the capability of agglutinating malignant cells in vitro. We studied the binding of fluorescein isothiocyanate-conjugated con A to formalin-fixed, paraffin-embedded malignant melanomas and nevocellular nevi. Both malignant melanoma cells and nevus cells emitted partial or circumferential, cytoplasmic rim, apple green fluorescence. There was no demonstrable difference between fluorescence distribution or intensity between the two groups. Control, unstained tissue specimens yielded a brilliant nuclear and nucleolar yellow-green autofluorescence, which is peculiar to melanoma cells and rare to absent in nevus cells. Fluorescein isothiocyanate-conjugated con A provided no clear differentiation between malignant melanomas and nevocellular nevi in fixed tissue. However, characteristic melanoma cell autofluorescence may prove to be of benefit for differentiating malignant melanocytic from benign nevocytic lesions.

Binding Sites↗