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The response of the atypically short adrenergic neurons in rabbit myometrium to 10-14 days of estradiol treatment (1 mcg/kg) was contrasted with neurons in untreated preovulatory adults in their appearance under electron microscopy. Estrogen doubled the size of the terminal axons originating from the preterminal nerve fiver and made them more consistent in size. Small granular vesicles containing transmitter were more evenly dispersed. Numbers and diversity of new ne urotubuli increased particularly along the length of the axon. The proportion of large vesicles 700-1200 Angstrom in diameter increased from 2%-3% to 5%-7% and numerous large agranular vesicles appeared. The large vesicles were occassionally in contact with the neurotubuli apparently continuous with neurotubuli plasma membrane.

SIF cells were traced from ganglia obtained during surgery using the formaldehyde induced fluorescence (FIF) method and electron microscopy. SIF cells are present in eyery ganglion studied, but sparce. The contain high amounts of catecholamines (CA) and unidentified peptides. Corresponding storage granules were found with EM. The cells were densely innervated with nonadrenergic axons. The role of SIF cells is discussed.

Potassium permanganate fixative is usually employed at pH 7.0. At this pH the amines in the granules of the adrenal medullary cells do not react with permanganate. When the pH was adjusted to 5.0, electron dense precipitates were seen in the amine granules of part of the medullary cells, probably noradrenalin containing cells.

The distribution of immunocompetent cells was analysed in allergic (nickel) and irritant (dithranol) patch tests using conventional transmission electron microscopy and labelling with monoclonal antibodies in an avidin-biotin immunoperoxidase study. The biopsies were taken 24 or 48 h after the allergen/irritant application. In allergic and irritant reactions, most inflammatory cells were OKT11 positive (pan T lymphocytes). The majority of these cells were also OKT4 positive (helper/inducer T lymphocytes), while the minority were OKT8 positive (suppressor/cytotoxic T lymphocytes). NK9 positive cells (natural killer cells) were observed in small numbers. The number of dendritic OKT6 and OKIal positive cells (Langerhans cells) in the epidermis was unaffected in allergic reactions. In irritant reactions, a normal number of OKT6 positive Langerhans cells was observed, while the number of OKIal positive cells had increased in the epidermis. Dithranol caused prominent fine structural changes in the mitochondria of the Langerhans cells, while the keratinocytes appeared largely unaffected. The present study indicates that allergic and irritant patch tests cannot be differentiated reliably using current immunohistopathological or electron microscopic techniques, in spite of the small differences observed.

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.

Midterm human fetal sympathetic ganglia were studied using the formaldehyde-induced fluorescence technique for demonstrating catecholamines, and after glutaraldehyde-OsO 4 or permanganate fixation for electron microscopy. The fluorescence technique indicated the presence of catecholamines in most of the developing neurons. After glutaraldehyde-OsO 4 fixation large granular vesicles were found in the perikarya, but a more specific technique for catecholamines, permanganate fixation, revealed no granular vesicles at this stage of development. This indicates that most of the catecholamines are loosely bound in a non-granular store during development.

Orfanos and Runne (9) were the first to report the fine-structural effects of an oral retinoid (Ro 10-9359) in psoriasis. They noted (a) enhanced inflammation with some cell degeneration in the malpighian layer, (b) extracellular accumulation of mucus-like material in the epidermis, (c) reappearance of keratohyaline granules and (d) normalization of other pathological changes both in the epidermis and the dermis.

A total of 40 patients with palmoplantar pustulosis (PPP) were initially treated with oral etretinate (Tigason) in an open trial with a maximum treatment period of 16 weeks. Remission, with only slight residual changes in some cases, was achieved in 26 patients (65%) who were randomized to either a low dose of Tigason or placebo. In the Tigason group, 7 of 11 patients were still in remission after 6 months while in the placebo group, remission persisted in 4 of the 10 patients who stayed in the study throughout the whole 6 months’ period. Alopecia led to stopping the treatment in 6 patients and desquamation of the healthy skin in 2 patients. Other side-effects were only mild. As a conclusion, Tigason shows a beneficial effect in the majority of patients with PPP and is better than placebo in preventing relapse of the disease but intolerable side-effects restrict its use in many patients.

The formaldehyde-induced fluorescence method was used for light microscopy and fixation in glutaraldehyde and osmium tetroxide for electron microscopy to study the effect of 75 mg/kg 6-hydroxydopamine on the paracervical ganglion of the rat uterus. No changes were observed in the fluorescence intensity of the ganglion. Ultrastructurally the ganglion cells and the synapses remained unchanged. The small, intensely fluorescent (SIF) cells were severely damaged, displaying large vacuoles with an irregular contour as well as smaller, more regular vacuoles studded with ribosomes. The granular vesicles showed a lower density of their central parts suggesting that their catecholamine content had diminished.

Subcellular fractions of the posterior pituitary of the rat were isolated by differential and density gradient centrifugation, and microsamples prepared for electron miscroscopy by KMnO4 or glutaraldehyde-OsO4 fixation. The nuclear fraction, P1 (1000 g x 7 min), was the main neurosecretosome (NSS) fraction and contained nuclei and mitochondria in addition to NSS (60%). The crude mitochondrial fraction, P2 (10,000 g x 20 min), contained free mitochondria (70%), NSS, unidentified membrane particles, fat droplets derived from pituicytes, neurosecretory granules (NSG) and synaptosomes, identified by the presence of synaptic membrane thickenings. Fraction P3 (32,900 g x 20 min) contained mainly free NSG, while fraction P4 (118,000 g x 30 min) had a high microsome content.

A new combination of freeze-drying, formaldehyde induced fluorescence method for catecholamines and autoradiography of water soluble substances was developed and tested with different tissues containing biogenic amines. The freeze-dried tissue pieces were fixed with vaporours paraformaldehyde and OsO4 before embedding procedure. The effect of OsO4-vapour on the formaldehyde induced fluorescence was tested. The method produces semi-thin sections in which the fluorescence is well preserved and the tissue lightly stained with OsO4 which also fixes the steroid hormones used for radioautography.

The number and nature of allergic occupational glove dermatoses were analysed. 542 cases of allergic contact dermatosis were diagnosed during 1974-1983. Amongst these, 68 (12.5%) were caused by rubber or plastic gloves. 2 patients had contact urticaria due to rubber gloves. Gloves were the main cause of occupational allergic rubber eczema, inducing 63 (58.3%) of 108 rubber eczema cases. 38 of them had positive reactions to rubber chemicals and glove material, 14 to glove material only, and 11 to rubber chemicals. 5 cases of allergic eczema from plastic gloves were diagnosed, all due to polyvinyl chloride (PVC). 2 cases of contact urticaria from natural rubber gloves were diagnosed by a provocation test. Epicutaneous testing with material of natural rubber gloves and rubber chemicals was negative. The present study shows that allergy to rubber gloves is usual, while allergy to plastic gloves is rare. Thus, plastic gloves should be used, when possible. Patch testing with protective gloves should always be used when patients develop prolonged hand dermatitis and where the possibility of glove eczema exists.

A 35-year-old machinist developed hand eczema from contact allergy to dibutylthiourea, a compound found in a paint and glue remover. Light and electron microscopy of his positive patch test was consistent with allergic contact dermatitis, showing Langerhans cell-mononuclear cell contacts in the epidermis.

Immunocompetent cells are invariably seen in psoriatic lesions, although their role in the pathogenesis of psoriasis is not known. There are several contradictory reports about the number and function of peripheral blood lymphocytes in psoriatic patients [1, 2]. The findings in peripheral blood, however, are far from being pathognomonic for psoriasis. To the best of our knowledge there are no reports about the in situ characterization of lymphoid cell subclasses in psoriatic skin as demonstrated by modern immunohistochemical methods, except those by Haftek et al. [5, 6] concerning Langerhans cells. Oral retinoids, especially etretinate, have proved beneficial in skin disorders characterized by disturbed epidermal proliferation and keratinization [11]. The exact mode of action of the retinoids is unknown, although they are known to stimulate cytotoxic T-lymphocyte induction [3] and to affect Langerhans cells [8, 14, 15]. In order to study the involvement of Langerhans cells and lymphocyte subclasses in pso

3 female workers in a brush factory developed contact allergy from a 2-component epoxy glue containing epoxy resin (37% w/w), reactive diluents: i.e., l,4-butanediol diglycidyl ether (BDDGE) 3%, glycidyl ethers of aliphatic alcohols (Epoxide 8) 0.03% and phenyl glycidyl ether (PGE) 0.01%: and inert fillers. All 3 patients were positive to the resin component of the glue and to BDDGE, indicating that BDDGE was the main allergen. 2 of the patients reacted to PGE, but none to the 3rd reactive diluent (Epoxide 8) in the glue. 2 of the patients did not react to epoxy resin, indicating that BDDGE may be an even stronger sensitizer in humans than epoxy resin, and that it does not cross-react with epoxy resins. Permeation studies revealed that BDDGE penetrates disposable PVC and rubber gloves in less than 30 min; thus, contaminated gloves should be replaced immediately. Reactive diluents should be included in patch test series if contact allergy to epoxy products is suspected.

The inflammatory cell infiltrates in scalp skin of 35 patients, 20 with alopecia areata (AA), 7 with totalis, and 8 with universalis were characterized with the ANAE (alpha-naphthylacetate esterase) marker, monoclonal antibodies, and electron microscopy. As demonstrated by the ANAE staining, no clear difference in the main lymphocyte subclasses (T and B cells) or macrophages was seen between the different types of alopecia or as compared to control patients' scalp skin. However, T lymphocytes and macrophages were seen most frequently and in greater numbers perivascularly and infiltrating the hair bulb in those cases of AA where active hair loss took place. Using monoclonal OKT (OKT-3, -4, and -8) antibodies and the avidin-biotin immunoperoxidase method on frozen sections, a concentration of OKT-8 reactive cells (suppressor/cytotoxic T cells) was seen peribulbarly and invading the hair infundibulum. The cells affecting the hair infundibulum were further studied by electron microscopy. They could be classified into three main types: small lymphocytes (60%), macrophages (30%) and cells closely resembling large granular lymphocytes (LGL) (10%). LGL have previously been considered to be human natural killer (HNK) cells. Thus the hair follicle seems to be the target for the cellular immune response in alopecia. Whether HNK cells participate in the destruction of hair bulbs remains to be investigated.

Oral retinoids — derivatives of vitamin A — have recently been found to be effective in the treatment of dermatoses showing hyperproliferation and disturbed keratinization (6). In previous studies the combination of retinoid and PUVA has given good results in the treatment of psoriasis with reduced UVA doses (3, 4, 9).

SUMMARY The light and electron microscopic structure of pityriasis rubra pilaris (PRP) is described in five patients. Hyperkeratosis, hypergranulosis, keratotic plugs in the follicular openings, acanthosis and focal parakeratosis were observed. A moderate perivascular infiltrate was seen in the upper dermis. Electron microscopy revealed moderately activated keratinocytes, a decreased number of tonofilaments and desmosomes, enlarged intercellular spaces, parakeratosis with lipid-like vacuoles and a large number of keratinosomes. Lymphoid cells were present in the epidermis in moderate numbers. At the dermo-epidermal junction, the basal lamina was focally split, containing gaps. Etretinate therapy produced moderate to marked clinical improvement. The histological picture improved but the typical signs of PRP, including follicular plugging, persisted. Ultrastructurally the cellular activity and the amount of hyperkeratosis and parakeratosis decreased, while increases in keratinosomes, intercellular substance, microvilli and desmosomes were observed during treatment.

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.

The ultrastructure and protein content of the five subfractions of the crude mitochondrial fraction from the brain stem of the 1-day old and adult rat was examined. The morphological composition of the subfractions after fixation in glutaraldehyde and osmiumtetroxide in the adult rat brain stem resembled that previously reported for the whole brain; synaptosomes sedimented in a sucrose gradient in subfractions C and D. In the 1-day old rat, mature synaptosomes were found in subfractions A, B, C and D; E contained mainly free mitochondria. 80–95% of the processes in the adult and 10–30% in the 1-day old rat contained synaptic vesicles which were of four types: (1) small agranular vesicles (2) large dense core vesicles (3) large agranular vesicles (4) coated vesicles. Pre- and postsynaptic membrane thickenings were demonstrated in many nerve-ending particles. In the subfractions of the 1-day old rat the protein content was one half and the distribution resembled that in the adult. Evidently nerve endings develop faster in the brain stem than in cortical areas; a serotoninor adrenergic origin of the early synaptosomes is suggested.

Permanganate fixation has been considered a specific means of demonstrating the granular pool of monoamines in electron microscopy. Our recent observations revealed that, surprisingly, the monoamines in the adrenomedullary cells are not visualized with conventional permanganate fixation at neutral pH. Acid permanganate did, however, demonstrate the noradrenaline cells. Permanganate also demonstrates the endoplasmic reticulum, which might be another storage site for monoamines.

An allergological examination, including prick tests, scratch chamber tests, patch tests, and RAST tests, was performed in 83 consecutive patients exposed to isocyanates. Three cases of allergic contact dermatitis from isocyanates have been detected: the first patient was allergic to isophorone diisocyanate and trimethyl hexamethylene diisocyanate, the second to 4,4′-diphenylmethane diisocyanate (MDI) and toluene 2,4-diisocyanate (TDI), and the third to HDI and its prepolymer Desmodur-N. To our knowledge, this was the first patient reported to have allergic contact dermatitis from HDL The optimal patch test concentrations were 2%–5% in petrolatum for TDI and MDI, and 0.1%–0.2% in petrolatum for HDI, whereas 0.5% was irritant.

Three types of monoamine-storing cells were fixed with permanganates and analyzed ultrastructurally. The SIF cells contained the typical granulated vesicles characteristic of monoamines. On the other hand, both the catecholamine-storing cells in the adrenal medulla and the mast cells were devoid of a dense core in their monoamine vesicles. This is surprising, since permanganate is considered a reliable means of demonstrating monoamines at the fine structural level. The significance of this finding is discussed against the close relationship between SIF cells and cells of the adrenal medulla. Because permanganate as a fixative is widely used in monoamine fine structural cytochemistry, the present findings undoubtedly need further clarification.

Brightly fluorescent paraganglia were found in the retroperitoneal tissue of adult man. The histofluorescence properties of the paraganglia indicate the presence of tryptophyl peptides, which might be of endocrine importance.

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.

† 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. (Arch Dermatol1988;124:551-554)

The vacuolated neurons (VN) of the main hypogastric ganglion of the male rat were studied using the formaldehyde-induced fluorescence (FIF) method for the histochemical demonstration of catecholamines. Microspectrofluorimetry was performed to identify the fluorophores and to quantify the FIF. The thiocholine method (Koelle-Gomori) was used to demonstrate acetylcholinesterase activity. The fine structure of the VN was studied using glutaraldehyde/OsO4 fixation. (1) In the untreated adult male rat VN represent only a small population of the total number of hypogastric neurons (0.8--1.2%). The vacuoles are similar to those of the VN from the corresponding female ganglion. (2) The VN are considered to be adrenergic due to the nature of their fluorophore, indicating a primary catecholamine. (3) The first VN appear in the hypogastric ganglia at the age of 7 weeks. After testosterone administration to young rats, VN are found at the age of 4 weeks. (4) The basic fine structure of the VN is similar to that of other ordinary neurons of the hypogastric ganglia. (5) The content of the vacuoles could not be identified. (6) Indications of degeneration were not observed in the VN. (7) The VN are interpreted as being a functional stage of the "short" adrenergic neurons, which are under the control of steroid hormones. (8) Fifteen months after castration, no VN could be found in the hypogastric ganglia, while their number was normal in the corresponding control animals.

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.

The histochemistry and fine structure of human fetal superior cervical ganglion has been studied in 5 fetuses aged from the 13th to the 15th week.

Two new types of structure of the cytoplasm of an autonomic neuron were described: (1) Inclusions of the rough ergastoplasmic reticulum, which were named “ergastosomes”, contain finely granular material with moderately electron opaque staining with both glutaraldehyde-OsO4 and KMnO4 fixations. A short comment was made on the nature of the contents of the ergastosomes. (2) Tubular formations of endoplasmic reticulum were found in the axons and/or dendrites of the paracervical ganglion.

A study was made of the ultrastructure of the paracervical (Frankenhauser) ganglion of the newborn rat, using immersion fixation by glutaraldehyde (2.5%) followed by OsO4 (1%), or KMnO4 (3%) fixation. The cells containing dense—core vesicles were divided into three groups: (1) primitive sympathetic cells, (2) cells containing some dense-core vesicles 700–1100 A in size and structurally resembling sympathetic neurons, called principal neurons, and (3) cells containing many dense-core vesicles with a larger, darker dense core, 800–2000 A in diameter, called granule-containing cells. Using glutaraldehyde-osmium fixation, the principal neurons were further divided into dark and light cells on the basis of electron opacity of the cytoplasmic matrix. The granule-containing cells were believed to correspond to the small, intensely fluorescent cells (SIF-cells) previously described using the formaldehyde-induced fluorescence technique. On the basis of the amount of granules, the granulecontaining cells were classified as mature or maturing SIF-cells and as more primitive SIF-cells, and developing sympathicoblasts. The development of synapses in autonomic ganglia was discussed.

The ultrastructure of the rat paracervical (frankenhauser) ganglion was studied during postnatal development after immersion or perfusion fixation with the glutaraldehyde, followed by postosmification. Three different neuronal cell types were found in the ganglion: (1) Primitive sympathetic nerve cells. They had a “primitive” structure and contained, in one section, one to two dense cored vesicles (DCV) of 700–1100 A in diameter. They were not found after the fourth day of postnatal development. (2) Principal neurons grew in size during the whole period of postnatal development. Part of them were already well developed in the ganglia of the newborn rat, and no particular changes in the content of their cytoplasmic organelles occurred thereafter. (3) Small granule-containing (SGC) cells. They usually occurred in small groups, often close to blood capillaries of the fenestrated type and were sometimes devoid of their satellite cell sheath in this region. They became slightly smaller in size as the animal aged. The size of their granulated vesicles (GV) varied mainly between 800–1400 A in all age groups in most of the cells. In addition, another type of SGC-cell containing larger GV up to 3000 A in diameter were observed in the ganglia of 32-day old and older rats.

Publisher Summary This chapter studies the developmental aspects of interesting ganglion, using the formaldehyde-induced fluorescence method for histochemical demonstration of catecholamines and the copper thiocholine method for localization of cholinesterases. Development of cholinesterase activity in the ganglia has been studied relatively little using histochemical methods. Light microscopy has been used to study this development in the dorsal root ganglion of the chicken and rat and electron microscopy in the dorsal root ganglion of the rabbit and the human fetus. Using electron microscopy, the development of cholinesterase activity has been studied in the neural tube and dorsal root ganglion of the rabbit embryo and human fetus. The enzyme appeared very early in development, just before the onset of morphological differentiation of the neuroblast. On the other hand, most of the electrophysiological work, using stimulation of the parasympathetic nerves has failed to cause action potentials in the uterus. However, some reports have also appeared favoring the parasympathetic nervous system control of the uterine function.

The distribution of nerves of the uterus containing acetylcholinesterase (AChE) and catecholamine (CA) was studied with light microscopic histochemical techniques after sympathectomy, parasympathectomy, and removal of the paracervical ganglion in the rat. A rich plexus of AChE-containing nerves was present both in the myometrium and around the uterine blood vessels. Nerve fibres exhibiting CA fluorescence were abundant around the blood vessels, but only sparse in the myometrium. Sympathectomy resulted in the disappearance of CA-containing perivascular nerve fibres but left intact the extravascular myometrial nerve fibres: those containing CA and those containing AChE. Parasympathectomy caused a slight decrease in the perivascular AChE-containing fibres. On the other hand it had no effect on the myometrial AChE- or CA-containing nerve fibres. Bilateral destruction of the paracervical ganglion resulted in the complete disappearance of AChE- and CA-containing fibres, both around the blood vessels and in the myometrium.

• The uninvolved skin of patients with psoriasis was examined microscopically. Atypical nuclear features in keratinocytes and melanocytes were found in about half of the patients. The patients treated with psoralens and UV-A (PUVA) had significantly more of these changes than did patients without PUVA treatment, and the risk was dose dependent. Previous arsenic treatment and x-ray irradiation seemed to have a similar effect. The changes may have been due to the shortwave UV range of the light source. (Arch Dermatol1983;119:904-909)