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Biomedical subjects

L Kanerva

Publications and source records attributed to L Kanerva.

At least 217 records · Page 12Linked to original sources
PubMed1990

Occupational dermatoses from epoxy resin compounds.

This study comprises 40 patients with skin disorders from current or previous occupational exposure to epoxy resin compounds (ERC) during 1984-1988. ERCs were the 3rd most common cause (32 of 264 cases: 12.1%) of currently relevant allergic contact dermatitis: 23 cases from epoxy resins based on the diglycidyl ether of bisphenol A (DGEBA-ERs), 5 from reactive diluents, 1 from amine hardeners (DETA), and 3 from epoxy acrylates. 2 cases (0.8%) of irritant contact dermatitis were due to ERCs. Methyl hexahydrophthalic anhydride (MHHPA, an epoxy hardener) caused 1 case of contact urticaria. Previously relevant occupational allergic contact dermatitis from DGEBA-ERs was detected in 5 cases. On patch testing, ERC allergens gave the following positive reactions: epoxy resin of the standard series in 35 cases (4.0% of 870 tested), epoxy reactive diluents in 10 (7.1% of 140), cycloaliphatic epoxy resins in 4 (11.1% of 36), epoxy acrylates in 4 (4.5% of 88), and amine compounds commonly used as epoxy hardeners in 17. Despite extensive patch test series, testing with patients' own ERCs remains important.

Chromatography, Gas↗
PubMed1990

Electron microscopic observations of dyskeratosis, apoptosis, colloid bodies and fibrillar degeneration after skin irritation with dithranol.

Dying cells undergo coagulative necrosis or apoptosis. In the skin, apoptosis is known to occur in graft-versus-host reactions, in lichen planus, during regression of plane warts and neoplasms, and after physical injury caused by ultraviolet light resulting in sunburn cells. The present study shows that primary skin irritation also causes apoptosis. Mild, or moderate-to-considerable, dithranol irritation of healthy uninvolved human skin caused focally coagulative necrosis of keratinocytes and also apoptosis of scattered keratinocytes, i.e. condensation of chromatin and cytosol, clumping of tonofilaments and budding of membrane-bound cell fragments. These apoptotic cell fragments were engulfed in the epidermis by macrophages. Colloid bodies were detected in the upper dermis and apparently represented nonphagocytosed apoptotic cell fragments that had dropped down from the epidermis. Dithranol also caused fibrillar degeneration of melanocytes and in some cases of Langerhans' cells, indicating that colloid bodies in the upper dermis could partly derive from these cell types. The significance of apoptosis in irritant contact dermatitis could be to maintain homeostasis of epidermis and counteract the hyperplastic response caused by irritant stimuli. Another possibility is that apoptosis was the response to an injury less severe than that causing necrosis.

Anthralin↗
PubMed1990

Long-lasting contact urticaria. Type I and type IV allergy from castor bean and a hypothesis of systemic IgE-mediated allergic dermatitis.

A unique urticarial type I patch-test reaction to castor bean that persisted for more than 48 hours and was followed by a delayed type IV reaction is described. Immunohistochemical and electron microscopic observations indicated involvement of eosinophils and IgE receptors on Langerhans' cells. The authors present a scheme for the role of Langerhans' cells in skin allergy.

Biopsy↗
PubMed1989

Electron microscopy of epidermal and dermal Langerhans' cells in long-lasting allergy patch tests.

In rare cases, normal allergy patch tests persist for weeks or months. Here, seven biopsies from six patients with long-lasting allergy patch tests, taken 15-75 days after allergen challenge, were analysed by transmission electron microscopy. In accordance with clinical expression of the test site, fine structural evidence of persistent activity of immunocompetent cells in the epidermis and dermis was observed. Moderate numbers of exocytic lymphocytes and macrophages were seen in the epidermis. Langerhans' cells (LC) appeared active, and LCs with Birbeck granules were detected both in the epidermis and the dermis and were also seen to cross the dermoepidermal junction. LC-mononuclear cell contacts were more frequent in the epidermis than is normal in allergy patch tests. A strong infiltrate of lymphocytes, macrophages, fibroblasts, mast cells, and cells resembling LCs but devoid of Birbeck granules, i.e. indeterminate cells, was seen in the upper dermis. Less than 10% of the dermal cells showing the fine structural appearance of LCs had Birbeck granules, as seen in a single section. Both indeterminate cells and LCs were apposed by lymphocytes in the dermis, often in a rosette-like fashion. The present paper is descriptive but gives background to the understanding of events in long-lasting allergy patch tests. However, the reason for and the basic mechanisms of long-lasting allergy patch tests are not known. A defect in down-regulation of the contact hypersensitivity reaction and/or a constant antigen stimulation could be responsible for the persistence of these allergy patch test reactions.

Epidermis↗
PubMed1989

Clinical, immunohistochemical, and electron-microscopic findings in gold dermatitis.

The clinical, immunohistochemical, and electronmicroscopic features of 13 consecutive patients with gold dermatitis were analyzed: 12 developed an eczematous dermatitis and one a lichenoid dermatosis. The patients had received intramuscular sodium aurothiomalate therapy from 1 month to 4 years before the dermatitis broke out. After cessation of gold therapy, the dermatitis persisted for 1-11 months. A relatively sparse perivascular mononuclear cell infiltrate was found in the affected skin in all cases. With immunoperoxidase staining, most of the infiltrating cells were shown to be OKT-4-positive T-helper lymphocytes. A majority of the infiltrating cells were Ia, i.e., HLA class II antigen, positive. Clearly increased numbers of dermal OKT-6-positive Langerhans' cells were also seen. In epidermis, on the contrary, the expression of both OKT-6 and Ia markers on dendritic cells was decreased. However, electron-microscopic examination revealed large numbers of macrophage-like cells and the Langerhans cells were activated, often in apposition to mononuclear cells within the epidermis. No correlation was observed between the immunohistological findings and the amount of gold received, the duration of gold therapy, and the interval between the last gold injection and biopsy, respectively, although peripheral blood eosinophilia was more common during 5-10 months of gold therapy. There were no specific findings in the patients in whom dermatitis lasted several months after discontinuation of the therapy. Our findings support the view that immunological mechanisms operate in the development of gold dermatitis, although the exact mechanisms remain unknown.

Adolescent↗
PubMed1989

Ichthyosis with laminated membrane structures.

Clinical, light-microscopic, and electron-microscopic features of a new type of ichthyosis are presented. The ichthyotic disease of a 75-year-old woman appeared in early childhood as dry and scaly skin. It slowly progressed to thickened and folded hyperkeratosis on her neck and axillae. The skin on the other parts of her body was shiny, red and hard. Her physical development was normal. Light microscopy showed acanthosis and papillomatosis with hyperkeratosis. The granular cells were vacuolated. Electron microscopy revealed diagnostic changes, i.e., concentric or parallel lamellar membrane structures and amorphous material in upper epidermal cells. Corresponding lamellar material was also seen in the cornified cells. The keratinosomes were abnormal and a hypothesis is presented indicating that a defect in keratinosome formation results in vacuolization and abnormal desquamation in this disease. According to the current classification, the present type of ichthyosis is one subgroup of lamellar ichthyosis. We have called it ichthyosis with laminated membrane structures, because they are electron-microscopically diagnostic. The mode of inheritance is unknown.

Aged↗
PubMed1989

Allergic contact dermatitis from dental composite resins due to aromatic epoxy acrylates and aliphatic acrylates.

7 patients were occupationally sensitized to dental composite resin products (DCR): 6 dental nurses and 1 dentist. All had a positive patch test to their DCR. 2 independent types of allergy were seen; (a) aromatic epoxy acrylate, and/or (b) aliphatic acrylates. 4 out of 5 patients reacted to BIS-GMA, the most widely used aromatic epoxy acrylate in DCR, but not the dentist. She and 2 dental nurses were allergic to aliphatic acrylates, including triethylene glycol dimethacrylate (TREGDMA) and triethylene diglycol diacrylate (TREGDA). 4 patients were allergic to epoxy resin (ER) (containing mainly MW 340), possibly an impurity in some DCR. 2 patients were also allergic to methyl methacrylate (MMA): the dentist, had been exposed to MMA, but the nurse's exposure was uncertain. 1 patient was also allergic to rubber gloves, 2 to rubber chemicals but not their gloves, and 5 to disinfectants used. diagnosis was delayed as long as 13 years in spite of previous patch testing. Dermatologists need to use the patients' own DCR and the (meth)acrylate series for patch testing. No dental nurses could continue their occupation, but the dentist could occasionally handle DCR if wearing PVC gloves. Dental personnel need to know about the risks of DCR, and use no-touch techniques and protective gloves.

Acrylic Resins↗
PubMed1989

Histopathological study of transient acrodermatitis enteropathica due to decreased zinc in breast milk.

Two children, one born prematurely and the other born at full term developed acrodermatitis enteropathica due to marginal or low levels of zinc in their mothers' breast milk. Skin from both patients was studied with light and electron microscopy. The most characteristic light microscopic features were parakeratosis, absence of the granular layer, and pallor of the upper epidermal cells. Normal flattening of the upper Malphighian cells did not occur. Electron microscopic examination revealed that keratohyalin was decreased to absent, and the upper malpighian cells were edematous with vacuoles and large numbers of ribosomes, but small numbers of tonofilaments. Large amounts of keratinosome-derived-lamellae were found in the intercellular spaces in the keratinization area. The keratinosome-derived-lamellae were focally intermingled with opaque lipid plaques or myelin figures, probably derived from keratinosomes. The electron microscopic findings show abnormal keratinization and suggest that it is related to a disturbance of keratinosome metabolism due to zinc deficiency.

Acrodermatitis↗
PubMed1989

Circular and branched Birbeck granules and cytomembrane blebbing in Langerhans' cells after dithranol irritation.

Mild dithranol irritation of healthy human skin has a stronger effect on the fine structure of Langerhans' cells (LC) than on that of other epidermal cells, causing mitochondrial enlargement and disruption of the cristae of LCs. With a stronger dithranol irritation, LCs were even more affected resulting in circular and branched Birbeck granules (BG) and blebbing of the LC cytomembrane. More often than is normal, BGs were contiguous with the LC cytomembrane. Electron microscopic observations indicated that blebbing and the abnormal BG formation were associated phenomena, in accordance with the hypothesis that BGs are endocytotic organelles formed from the cytomembrane.

Anthralin↗
PubMed1988

Occupational skin disease in Finland. An analysis of 10 years of statistics from an occupational dermatology clinic.

An analysis of 10 years (1974-1983) of statistics was carried out at the Institute of Occupational Health, Helsinki, Section of Dermatology, which is devoted to occupational dermatology. A total of 1,082 cases of occupational skin diseases were diagnosed during this period. Allergic (50.1%) and toxic eczema (47.1%) comprised the majority of occupational cases of dermatosis. The most frequent causes of allergic occupational eczemas were rubber chemicals (19.9%), chromates (18.8%), and epoxy resins (13.1%). If the metals (chromium, nickel and cobalt) were considered as a group, they formed the largest category (28.4%), followed by the plastic materials (27.7%). Detergents (37.8%), followed by organic solvents (16.1%), were responsible for most of the irritant (toxic) eczemas. Occupational skin diseases currently make up about 20% of all occupational diseases in Finland, but the percentage is decreasing.

Allergens↗
PubMed1988

Occupational allergic rhinitis from guar gum.

Three cases of allergic rhinitis from a vegetable gum, guar gum, have been detected. Two subjects were exposed to fine guar gum powder (Emco Gum 563, Meyhall Chemical AG, Switzerland), an insulator in rubber cables, when opening cables in a power cable laboratory. After 1-2 years' exposure the patients developed rhinitis. Scratch-chamber tests, nasal provocation tests, nasal eosinophilia and a RAST test proved their allergy. A third subject developed allergic rhinitis from another guar gum product (Meyproid 5306, Meyhall Chemical AG) after 2 years' exposure in a paper factory. A positive skin test and nasal provocation test confirmed the diagnosis. A fourth case of possible allergy to guar gum after exposure to Meyproid 5306 in a paper factory is also presented. No final diagnosis was reached in this case (in 1974). The present subjects, only one of whom was atopic, developed allergy within 2 years, although their exposure to guar gum was not especially heavy. Therefore, when handling guar, adequate ventilation facilities should be provided and protective clothing, including a respiratory mask, should be worn.

Adult↗
PubMed1988

Sensitization to patch test acrylates.

Data on allergic contact dermatitis from acrylates and 4 patients sensitized during routine patch testing are reported. During 1982-1985, we used 7 different acrylates for tests. 1 patient out of 22 (= 4.5%) was sensitized to ethyl acrylate and butyl acrylate (1% pet.). Since September 1985, we have used a commercial (meth)acrylate series containing 28 substances. 3 of 24 patients tested became sensitized to ethyl acrylate, 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate (0.5% pet.). Because active sensitization with acrylates can be very harmful, it may be necessary to use lower concentrations than recommended. Currently, we test ethyl acrylate, 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate at 0.167% pet.

Acrylates↗
PubMed1988

Immunohistochemistry of lymphocytes and Langerhans' cells in long-lasting allergic patch tests.

A long-lasting allergic patch test is a "normal" allergic patch test that remains positive for weeks or months. An immunohistochemical study of immunocompetent cells in the skin in this rare type of patch tests was performed. Most inflammatory cells were T11 positive T-lymphocytes. The majority of these cells were of the helper/inducer phenotype (T4+), but a relative increase of T8+ cells as compared to the initial (1-2d) stages of allergic patch tests was observed. T6+ Langerhans' cells (LCs) were normal or increased in number in the epidermis, while very few dendritic cells displayed Ial antigen in the epidermis, indicating loss of Ial-staining of LCs. High to very high numbers of T6+ cells were found in the dermis. An inflammatory reaction of hair follicles with moderate numbers of T6+ cells in the peribulbar infiltrate was observed indicating that hair follicles might act as shunt pathways for allergens. A defect in down regulation of the contact hypersensitivity reaction and/or a constant antigen stimulation could be responsible for the long-lasting allergic patch tests.

Allergens↗
PubMed1988

Electron microscopy of tubuloreticular structures in allergic patch test. Observations with 2,3-epoxypropyl trimethyl ammonium chloride.

Tubuloreticular structures (TRS) are intracellular tubular inclusions that can be detected by means of electron microscopy. TRS have earlier been found in autoimmune, viral and neoplastic diseases. Here the occurrence of TRS is for the first time described in allergic patch tests, where they were detected in dermal macrophages. TRS are believed to be reaction products of metabolically active cells, and the TRS described here are probably formed as a result of the activation of the immune system in allergic patch tests.

Dermatitis, Contact↗
PubMed1988

Clinical and ultrastructural effects of acitretin in Darier's disease.

Thirteen patients with Darier's disease with a mean extent of the lesions of 29.4 +/- 10% of the total skin area were treated with acitretin (the main metabolite of etretinate) for 16 weeks. The dose was 30 mg/day during the initial 8 weeks and was later adjusted individually to 10-30 mg/day in order to achieve optimal results. Three patients cleared completely, 7 patients showed marked improvement and 3 patients became slightly better during treatment. The mean extent of the lesions after the treatment was 7.3 +/- 8% of the skin area. Despite good clinical clearing, the improvement at the ultrastructural level was incomplete in the 3 patients studied by electron microscopy. Normal stratification did not develop and the size and number of desmosomes remained reduced. The main side effects during treatment were pruritus in 5 patients, diffuse alopecia in 2 patients and marked elevation in serum triglycerides in 4 patients. On the basis of this study, acitretin would seem to be a useful alternative to etretinate for the treatment of Darier's disease.

Acitretin↗
PubMed1988

Epidermolysis bullosa simplex associated with muscular dystrophy with recessive inheritance.

Epidermolysis bullosa with unusually severe clinical features was associated with progressive muscular dystrophy in two siblings. Light and electron microscopic examination revealed an intraepidermal cleavage confirming that this mechanobullous disease belonged to the epidermolysis bullosa simplex group. This may represent a new disease entity inherited in an autosomal-recessive fashion.

Adolescent↗