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Biomedical subjects

S T Zaynoun

Publications and source records attributed to S T Zaynoun.

At least 19 recordsLinked to original sources
PubMed1992

Primary localized cutaneous amyloidosis.

Fifty-seven patients with primary localized cutaneous amyloidosis (PLCA) were clinically and histopathologically reviewed. Two-thirds of patients had macular amyloidosis (MA). Intermediate cases having macular lesions with micropapules and/or lichens were identified. A spectrum for the disease is proposed, in which the less itchy classical macular variant occurs at one end and the very pruritic traditional lichen variant at the other. The salient histopathologic findings were similar in the macules, micropapules, and lichens, but were more prominent in the lichens. These consisted of hyperkeratosis, keratinocyte degeneration, satellite cell necrosis, and basal cell destruction. Amyloid deposition in the dermal papillae with transepidermal elimination, dermal melanophages, and superficial perivascular inflammation were also present. These changes represent an interface dermatitis of the vacuolar type. PLCA may be categorized under the group of dermatoses characterized by a lichenoid tissue reaction; inflammation may play a key role in mediating these disorders.

Adolescent↗
PubMed1990

Lichen planopilaris: a clinicopathologic study.

Three clinicopathologic variants of lichen planopilaris are described. The first is characterized clinically by individual keratotic follicular papules and histologically by a lichenoid inflammatory cell infiltrate confined to the follicular epithelium. The second variant consists of erythematous to violaceous plaques, some of which show follicular prominence; the histologic appearance is that of a lichenoid inflammatory cell infiltrate that affects both follicular and interfollicular areas. The third variant manifests as follicular papules of the scalp with concomitant or subsequent cicatricial alopecia. In this variant the histologic hallmark is a lichenoid, follicular and interfollicular inflammation, associated with or followed by scarring. Overlap among the three variants exists, and hence the concept of a disease spectrum ranging from pure follicular involvement without evidence of clinical scarring to cicatricial alopecia of the scalp is advocated.

Adult↗
PubMed1990

Acrokeratoelastoidosis.

Two cases of acrokeratoelastoidosis comprised of smooth shiny papules on the hands, feet and legs, are reported. Focal acral hyperkeratosis, degenerative collagenous plaques of the hands and keratoelastoidosis marginalis of the hands are three closely related conditions.

Adult↗
PubMed1985

Acute febrile neutrophilic dermatosis (Sweet's syndrome): case report and review of the literature.

An 8-month-old male infant had fever, polymorphonuclear leukocytosis, and tender, firm, elevated erythematous plaques on his face, trunk, and extremities. Histologic examination revealed a dense, perivascular, polymorphonuclear, inflammatory cell infiltrate with nuclear dust in the dermis and intrafollicular abscesses. The rash responded promptly and dramatically to oral corticosteroids. In our opinion, these features represent a distinctive hypersensitivity reaction consistent with acute febrile neutrophilic dermatosis (Sweet's syndrome). It seems that Sweet's syndrome has two age peaks: infancy and middle age. In the former, no sex predilection and no underlying malignancy have been recorded. In the latter, females are preponderantly affected and an associated underlying malignancy has been described.

Acute Disease↗
PubMed1985

Partial (localized) lipodystrophy. Report of a case with muscle and skin abnormalities.

The light and electron microscopic myopathologic and dermatopathologic features in one patient with the partial (localized) type of lipodystrophy are described. The myopathologic changes involve both the contractile elements and the intracellular organelles, especially mitochondria that show hyperplasia and structural alterations of cristae. The dermatopathologic changes consist of a reduction in subcutaneous fat, intercellular edema, and the presence of intracytoplasmic lipid droplets. This is the first report in the literature in which the myopathologic features and detailed electron microscopy of skin in this condition are described. The myopathologic features of partial lipodystrophy are compared with those of congenital generalized lipodystrophy. It is proposed that a myopathy may be one of the manifestations of partial lipodystrophy.

Adult↗
PubMed1984

Ficus carica; isolation and quantification of the photoactive components.

The presence and levels of furocoumarins in several parts of Ficus carica including the milky sap, were investigated. The results show that psoralen and bergapten are the only significant photoactive compounds, and are present in appreciable quantities in the leaf and shoot sap but are not detected in the fruit or its sap. These compounds are more concentrated in the leaf sap compared to the shoot sap. The psoralen levels are several times higher than those of bergapten. Lower concentrations of both compounds are present in autumn compared to spring and summer. These findings suggest that the reaction is induced primarily by psoralen. The response can follow contact with the leaf and shoot sap but not with the fruit sap, and is expected to occur more frequently from exposure to the leaf sap. The higher content of both photoactive compounds in spring and summer is partly responsible for the increased incidence of fig dermatitis during these seasons. Ingestion of the fruit does not cause photosensitization and the absence of photoactive furocoumarins in the fruit and its sap remains unexplained.

5-Methoxypsoralen↗
PubMed1983

Extensive pityriasis alba: a histological histochemical and ultrastructural study.

Nine patients with extensive pityriasis alba were studied using histopathological and histochemical techniques and electron microscopy. There was a reduction in the density of functional melanocytes in the affected areas without any change in their cytoplasmic activity. The melanosomes tended to be fewer and smaller, but their distribution pattern in the keratinocytes was normal. Melanosomal transfer to keratinocytes was generally not disturbed. The histology was non-specific. Hyperkeratosis and parakeratosis were not consistently present, and it seems unlikely that they played a significant role in the pathogenesis of the hypomelanosis. A variable degree of intercellular oedema and intracytoplasmic lipid droplets were present. The hypopigmentation may thus be due primarily to the reduced numbers of active melanocytes and a decrease in number and size of melanosomes in the affected skin.

Adolescent↗
PubMed1981

Berloque dermatitis - a continuing cosmetic problem.

Despite the decline in the incidence of berloque dermatitis during the past decade, milder cases resulting from the presence of relatively small quantities of bergapten in perfumed cosmetics continue to occur. The resultant hyperpigmentation may have an atypical presentation leading to error in diagnosis. In addition, the condition can sometimes induce or aggravate melasma and may be responsible for other pigmentary disorders of the face and neck of questionable etiology such as poikiloderma of Civatte, Riehl's melanosis and pigmented peribuccal erythema of Brocq.

5-Methoxypsoralen↗
PubMed1977

A study of oil of bergamot and its importance as a phototoxic agent. I. Characterization and quantification of the photoactive component.

It is important in the technique of photopatch testing, using oil of bergamot, to have determined the concentration of the active psoralen, bergapten, so as to avoid false negative responses in the assessment of phototoxic reactions. Techniques for assessing the phototoxic components of oil of bergamot are described and quantitative analyses of bergapten, the only significant photoactive compound in the samples examined, are reported. The phototoxicity of bergapten was found to be nearly the same as that of xanthotoxin (8-MOP) in tests on human skin.

Coumarins↗
PubMed1977

The treatment of erythropoietic protoporphyria. Experience with beta-carotene.

In a group of 19 subjects suffering from erythropoietic protoporphyria the administration of beta-carotene appeared to produce improvement based on a subjective assessment of alterations in exposure times required to produce the symptoms and signs of the condition. This clinical improvement however failed to show a direct correlation with the prophyrin levels in blood and faeces, or with the estimation by phototesting of the minimal response dose within the action spectrum of 400-600 nm.

Adolescent↗
PubMed1977

A study of oil of bergamot and its importance as a phototoxic agent. II. Factors which affect the phototoxic reaction induced by bergamot oil and psoralen derivatives.

Using a standardized open photopatch test technique, the phototoxic reactions produced by bergamot oil bergapten (5-methoxypsoralen) the active component of the oil, and xanthotoxin (8-methoxypsoralen) were studied. The reaction was affected by a range of factors such as the vehicle (PMF or ethanol), the concentration of ethanol in the vehicle, the skin site, the interval between application of the psoralen and irradiation, the hydration of the skin, and the degree of natural or sun-induced pigmentation. Repeated photopatch testing at the same skin site produced an increase in sensitivity. Eye colour, natural susceptibility to suntanning, age, and sex, had no effect on the phototoxic response to psoralens.

Adolescent↗