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A N Sapadin

Publications and source records attributed to A N Sapadin.

At least 19 recordsLinked to original sources
PubMed2000

Collagen loss in photoaged human skin is overestimated by histochemistry.

It is well known that photoaged skin is characterized by increases in dermal matrix components that include glycosaminoglycans, proteoglycans and masses of abnormal elastic fibers accompanied by substantial collagen loss. Histochemical staining of such tissue gives the impression of "massive" loss of collagen and its replacement by these other matrix components. Early biochemical studies have lent support to this notion with a reported decrease in total collagen of approximately 45% compared to protected skin. More recent studies report considerably less, but varying, amounts of collagen loss. Rarely have the two approaches, histochemistry and biochemical analysis, been used in the same study to examine the same tissue. In this study, collagen loss was quantified biochemically in paired biopsies from sun-protected and sun-exposed arm skin of moderately photoaged female subjects (age 51-77 years). The values obtained were compared with histochemical and immunochemical findings. Quantitatively, collagen loss on a per mg protein basis was small compared to the histochemical appearance.

Aged↗
PubMed2000

Basement membrane alterations in psoriasis are accompanied by epidermal overexpression of MMP-2 and its inhibitor TIMP-2.

Psoriasis is most probably an inherited disease characterized by cell proliferation, angiogenesis, and an inflammatory process. The pathophysiology remains unknown, although an alteration in cell-cell and cell-matrix adhesion versus an autoimmune process has been proposed as the primary defect. Here, we show evidence of a new mechanism involving basement membrane alterations accompanied by keratinocyte overexpression of matrix metalloproteinase (MMP) 2 and tissue inhibitor of MMP-2 (TIMP-2) in both uninvolved and involved psoriatic skin. Immunocytochemistry with antibodies against collagen IV (alpha1, alpha2 chains) and laminins (alpha2, alpha5, beta1, gamma1 chains) revealed gaps, folding, and reduplication of the epidermo-dermal basement membrane. There was overexpression of MMP-2 in the cytoplasm of suprabasal keratinocytes. Gelatin zymography revealed pro-MMP-2 and its activated form, a-MMP-2, in both uninvolved and involved psoriatic skin, whereas pro-MMP-9 was only present in involved skin. TIMP-2 was expressed at the cell surface of psoriatic involved suprabasal keratinocytes whereas it was restricted to basal keratinocytes in uninvolved areas. Western blots showed a marked increase in a-MMP-2 and TIMP-2 in uninvolved and involved psoriatic skin although it was more pronounced in the latter. MT1-MP, known to activate pro-MMP-2, was increased in involved areas. In situ hybridization revealed strong signals of MMP-2 mRNA in both uninvolved and involved psoriatic epidermis. The overexpression of MMP-2 in uninvolved and involved psoriatic epidermis supports the concept that the primary alteration may reside in the keratinocyte. In addition, the presence of the activated form of MMP-2 could be responsible for cell-cell and cell-matrix changes noted in psoriatic epidermis.

Basement Membrane↗
PubMed2000

All-trans-retinoic acid-induced scrotal ulcerations in a patient with acute promyelocytic leukemia.

Induction therapy with all-trans -retinoic acid has been shown to improve the outcome of patients with acute promyelocytic leukemia, although some side effects occur. Dry skin and lips are among the most common cutaneous side effects. We report a case of scrotal ulcerations induced by all-trans -retinoic acid in an American patient; to our knowledge this is the first such case reported.

Antineoplastic Agents↗
PubMed2000

Dermatofibrosarcoma protuberans in two patients with acquired immunodeficiency syndrome.

Dermatofibrosarcoma protuberans (DFSP) is a locally aggressive cutaneous tumor of intermediate malignancy. Most commonly, it arises as an asymptomatic, indurated plaque on the trunk within which protuberant nodules develop over time. We describe its occurrence in two patients with human immunodeficiency virus, a previously unreported association. The first patient, a 41-year-old woman, complained of painful lesions around the left shoulder that developed within a scar from previous trauma to the area. The second patient, a 50-year-old man, developed a recurrent DFSP within the scar from a previous surgical procedure. Dermatofibrosarcoma protuberans was confirmed in both cases by the histopathologic and immunohistochemical findings.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Herpes zoster.

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AIDS-Related Opportunistic Infections↗
PubMed1999

Pseudoxanthoma elasticum: an update.

Pseudoxanthoma elasticum (PXE) is an inherited disorder of elastic tissue with many systemic manifestations. The disease varies widely in its degree of expression and inheritance patterns and is believed to be considerably underdiagnosed due to lack of familiarity with the condition among physicians. The purpose of this article was to provide an update on important topics in PXE. Common presentations of the disease as well as the histopathology are discussed. The genetics of PXE as well as the importance of early diagnosis and genetic counseling are addressed. Special areas of concern, such as PXE in childhood, are reviewed. Finally, the article concludes with management of the disease and current areas of research.

Humans↗
PubMed1998

Ultraviolet B radiation increases steady-state mRNA levels for cytokines and integrins in hairless mouse skin: modulation by topical tretinoin.

Chronically sun-damaged human skin has a wrinkled, aged appearance as a result of alterations in the dermal extracellular matrix. Secondary effectors such as cytokines and integrins may mediate the effects of UV radiation on the skin by regulating the synthesis of metalloproteinases and structural proteins including collagen. The aim of this study was to semi-quantify the steady-state mRNA levels of interleukin-1 alpha, tumor necrosis factor alpha, transforming growth factor beta, collagenase, stromelysin, collagen, and integrins (alpha, and alpha2) in the skin of hairless mice that were either treated with UV or concurrently treated with UV and topical tretinoin for 5 weeks. Total RNA was extracted from the skin of the mice, reverse transcribed to cDNA, and amplified by the polymerase chain reaction in the presence of 32P-dCTP using gene-specific primers. Results were normalized relative to glyceraldehyde-3-phosphate dehydrogenase levels. Steady-state mRNA levels of the cytokines and integrins were increased by UV radiation. Concurrent UV and topical tretinoin treatment superinduced the expression of interleukin-1, increased alpha 1, and decreased alpha 2 integrin expression. Immunofluorescence analysis showed increased dermal localization of beta 1 integrin in UV and tretinoin treated skin. These results suggest that cytokines and integrins may be involved in the mechanism of photo-damage.

Administration, Topical↗
PubMed1998

Paraneoplastic pemphigus with a pemphigus vegetans-like plaque as the only cutaneous manifestation.

Paraneoplastic pemphigus (PNP) is a recently recognized autoimmune mucocutaneous disease associated with a few unusual lymphoreticular neoplasms. Intractable stomatitis is the most constant clinical feature but the cutaneous presentations are characteristically variable. We describe a patient with PNP associated with chronic lymphocytic leukemia who presented with severe oral, laryngeal, and pharyngeal involvement. The only cutaneous finding was a pemphigus vegetans-like plaque, a previously undescribed manifestation. The plaque evolved from a flaccid blister that formed at a prior intravenous catheter site. The mucosal biopsy specimen demonstrated faint intercellular staining with IgG, whereas results for the cutaneous plaque were negative. Indirect immunofluorescence testing was positive on both monkey esophagus and rat bladder epithelium. Immunoprecipitation (IP) studies demonstrated a complex of 4 proteins with molecular weights of 250, 230, 210, and 190 kd, confirming the diagnosis of PNP.

Autoimmune Diseases↗
PubMed1998

Periumbilical pseudoxanthoma elasticum associated with chronic renal failure and angioid streaks--apparent regression with hemodialysis.

Pseudoxanthoma elasticum (PXE) is a heritable connective tissue disease involving progressive fragmentation and dystrophic calcification of elastic fibers. Periumbilical disease as the exclusive site of cutaneous involvement is most commonly seen in the rare entity termed periumbilical perforating pseudoxanthoma elasticum (PPPXE). Patients with this disorder are generally obese, middle aged, multiparous black women with hypertension. The cutaneous lesions are well-demarcated, hyperpigmented, periumbilical plaques with keratotic papules on the periphery. Extracutaneous manifestations have rarely been described. We describe a patient with periumbilical PXE associated with chronic renal failure and bilateral angioid streaks. Histopathologic examination demonstrated typical calcification of elastic fibers with additional amorphous calcium deposits in the superficial dermis. Transepidermal elimination was not present. Normalization of the serum calcium-phosphate product resulted in regression of the lesions--both clinically and histopathologically. The relation between PPPXE and hereditary PXE is discussed. The role of chronic renal failure in precipitating PPPXE is considered.

Aged↗
PubMed1998

Neurofibroma.

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Diagnosis, Differential↗
PubMed1996

Peeling agents and irritants, unlike tretinoin, do not stimulate collagen synthesis in the photoaged hairless mouse.

Tretinoin has been shown to stimulate the synthesis of collagen in photo-aged human and hairless mouse skin. It has been suggested that this partial reversal of photodamage by tretinoin is a consequence of low-grade inflammation. The purpose of this study was to compare the effect of tretinoin with a number of irritants and peeling agents on collagen synthesis. Hairless mice were irradiated thrice weekly for 10 weeks with UVB. In the 10-week postirradiation period, the mice were treated topically five times per week with tretinoin (0.05%), glycolic acid (10%), benzalkonium chloride (1.0%), sodium lauryl sulfate (5%), croton oil (5%) and the water - propylene glycol vehicle. Microscopic measurements showed that the tretinoin-induced zone of new collagen was twice the depth of that induced by irritants or vehicle. The salt-soluble collagen content was determined by HPLC analysis of hydroxyproline levels. Type III procollagen was quantified by radioimmunoassay. Tretinoin-treated skin had increased amounts of collagen and type III procollagen whereas irritant- and peeling agent-treated skins were similar to vehicle-treated controls. Immunofluorescence studies were confirmatory. These results demonstrate that these agents, unlike tretinoin, do not have the capacity to enhance collagen synthesis. Therefore, it is likely that the effect of tretinoin does not depend upon irritation.

Animals↗
PubMedDate not supplied

Souvenir from the Hamptons - a case of cutaneous larva migrans of six months' duration.

Cutaneous larva migrans is a distinctive serpiginous eruption caused by a reaction to burrowing hookworms. The infection is usually self-limited, normally lasting 2-8 weeks, but may persist for more than a year if misdiagnosed. Biopsies of the creeping eruption rarely reveal an organism. Thus, it is important for the infection to be recognized clinically, so that effective treatment may begin. We found topical thiabendazole to be fast and effective in treating this case of cutaneous larva migrans of six months' duration.

Adult↗