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Background: The usefulness of bone marrow cells in accelerating wound healing has not been evaluated despite increasing evidence that bone marrow contains mesenchymal stem cells that have multipotentiality to differentiate into various types of cells after they enter the microenvironment of a specific tissue (niche)., Objectives: To determine the effects of bone marrow cells and occlusive dressings in promoting wound healing in rats., Methods: We investigated by grafting, biopsy and immunohistochemistry whether various types of cells derived from green fluorescent protein (GFP)-transgenic rats would differentiate into wound component cells when administered topically on the wounds of rats. We also investigated whether topical application of bone marrow cells with an occlusive dressing would accelerate the healing of wounds with exposed bones, as measured by planimetry., Results: GFP-labelled bone marrow cells contained multipotent stem cells that sufficiently differentiated into wound myofibroblasts presenting with alpha-smooth muscle actin in granulation tissue. Other types of cells, including myocytes, adipocytes, peripheral blood cells from buffy coat and dermal fibroblasts, did not express myofibroblast characteristics morphologically or immunohistochemically. Application of bone marrow cells and an occlusive dressing accelerated the repair of wounds with exposed bones, compared with an occlusive dressing only or with the topical administration of bone marrow cells plus a semidry to dry dressing., Conclusions: Our study indicates that bone marrow cells accelerate the healing of wounds at least in part through their differentiation into wound myofibroblasts. Thus, treatment of wounds with bone marrow cells and a supportive occlusive dressing is effective in promoting the formation of healthy granulation tissue and also for the preparation of an ideal wound bed.

Background: Wounds with exposed bones caused by rheumatic diseases commonly result in amputation despite progress in our understanding of wound-healing mechanisms., Objectives: To determine whether an experimental therapy of bone marrow exposure, an occlusive dressing and subsequent grafting of epidermal sheets accelerates healing and reduces the need for amputation in patients with rheumatic diseases., Methods: Fifteen patients, including those with rheumatoid arthritis or systemic sclerosis, who had wounds with exposed bones were treated either with the standard procedure, consisting of local wound care, debridement with a scalpel, bed rest and parenteral antibiotics (n = 8), or with a newly developed experimental procedure (n = 7). In that new procedure, the affected bone was initially exposed by debridement with a scalpel, followed by partial excision with a bone scraper until bleeding was observed from the exposed bone. The lesions were immediately covered with an occlusive dressing, and were eventually treated with epidermal grafts obtained from suction blisters., Results: A comparison with standard therapy demonstrated that the time needed for wound healing was similar, but that the newly developed combination therapy reduced the risk of amputation (P = 0.020). No skin ulcers or erosions were observed for at least 1 year in five of seven patients (72%) due to the adoption of stable palmoplantar-type characteristics in grafts derived from the trunk epidermis., Conclusions: Our study indicates that exposure of bone marrow cells plus an occlusive dressing accelerates the healing of skin ulcers at least partly through the preparation of a healthy well-granulated wound bed and that subsequent epidermal grafting achieves site-specific differentiation through epithelial-mesenchymal interactions.

Background: Diabetic foot ulcers with exposed bones commonly result in amputation., Objectives: To determine whether exposure of bone marrow cells and subsequent grafting of epidermal sheets accelerates healing and reduces the need for amputation., Methods: Thirty-eight patients with chronic wounds caused by diabetes mellitus were enrolled in this study. Epidermal sheets obtained from suction blisters of each patient were grafted on to diabetic foot ulcers without exposed bones (n = 10) and were compared with the standard treatment of local wound care, debridement with a scalpel when indicated, bed rest and parenteral antibiotics (n = 8). In another group of patients, diabetic wounds with exposed bones were treated either with the standard procedure (n = 9) or with a newly developed experimental procedure (n = 11). In that new procedure, the affected bone was initially exposed by debridement with a scalpel, followed by partial excision with a bone scraper until fresh bleeding was observed from the exposed bone. The lesions were then immediately covered with an occlusive dressing, and finally the wound was covered with an epidermal graft of skin harvested from suction blisters. Patients in each group were matched with their counterparts by age, sex, wound size, wound infection and wound duration, to compare the time needed for total skin repair and rates of amputation., Results: Epidermal grafting significantly accelerated the healing of diabetic foot ulcers (P = 0.042) without exposed bones, with site-specific differentiation. The newly developed combination therapy resulted in the healing of all diabetic ulcers with exposed bones without the occurrence of osteomyelitis or the necessity for amputation (P < 0.0001)., Conclusions: Our study indicates that early aggressive debridement of diabetic foot ulcers with exposed bones down to a bleeding vascularized base and then grafting epidermal sheets significantly improves healing and reduces the rate of amputation.

Background: Anti-cancer effects of cyclooxygenase (COX)-2 inhibitors have been reported, but not fully investigated in skin and oral diseases. 5-aminolaevulinic acid (ALA)-based photodynamic therapy (PDT) for treating those patients with skin and oral lesions is a highly sophisticated procedure, but the incidence of disease recurrence after treatment is rather significant., Objective: To confirm that COX-2 could be a molecular target in adjunctive therapy to ALA-based PDT, we investigated (i) COX-2 expression in various skin and oral diseases, and (ii) the inhibitory effects on cellular growth of COX-2 selective inhibitor (nimesulide), ALA-based PDT and their combination on human oral squamous cell carcinoma (SCC) cell lines., Methods: A total of 129 biopsy samples from the skin and oral mucosal lesions were tested immunohistochemically for COX-2 expression. Then the in vitro effects of nimesulide, ALA-based PDT, and their combination were determined on two SCC cell lines, HSC-2 and HSC-4. Three different methods (MTT assay, double-staining for annexin V and propidium iodide, caspase-3/CPP32 fluorometric protease assay) were applied for evaluation of their inhibitory effects on these two cell lines., Results: Among the skin diseases, a considerable number of COX-2 high expressers were found in actinic keratosis (15 of 25, 60%), Bowen's disease (13 of 17, 76%) and extramammary Paget's disease (15 of 15, 100%). In contrast, only one of 33 (3%) basal cell carcinoma tumours was a COX-2 high expresser. Among the oral mucosal biopsies, the proportion of COX-2 high expressers increased gradually from hyperplasia (one of six, 17%) through mild dysplasia (five of eight, 63%) and moderate dysplasia (20 of 23, 87%) to severe dysplasia (two of two, 100%). Nimesulide had an inhibitory effect in vitro on HSC-2 (proven to be a COX-2 high expresser), but not on HSC-4 (a COX-2 non-expresser). While ALA-based PDT showed an inhibitory effect on both HSC-2 and HSC-4, most importantly the combination of nimesulide and ALA-based PDT demonstrated a significant synergistic effect on the cellular growth inhibition of only HSC-2, but not of HSC-4., Conclusions: Our study strongly suggests that COX-2 can be one of the molecular targets in treating various skin and oral diseases. The results from our in vitro experiments also prompt us to develop a new protocol with a combination of COX-2 selective inhibitor and ALA-based PDT for more effective treatment of those diseases.

Background: Topical immunotherapy with a contact allergen is effective in alopecia areata (AA). However, the mechanism of the effect is still unknown, and pretreatment prediction of the outcome of therapy in each patient remains difficult., Objectives: To predict the clinical effect of this therapy in AA patients, we investigated the relationship between clinical responses to topical immunotherapy and in vitro proliferative responses of peripheral blood mononuclear cells (PBMC) to T-cell stimulants., Methods: PBMC were taken from 67 AA patients before or during diphenylcyclopropenone immunotherapy and from 14 healthy controls, and proliferative responses to phytohaemagglutinin and staphylococcal enterotoxin B were evaluated by measuring [3H]-thymidine incorporation., Results: PBMC from the AA patients with a good clinical response to immunotherapy showed a normal level of proliferation, whereas PBMC from the poor responders showed a markedly suppressed proliferative response and interleukin (IL)-2 production, but increased IL-4 production compared with the controls., Conclusions: The proliferative response of PBMC to T-cell stimulants may be one of the indicators of the clinical effect of topical immunotherapy for AA.

The severity of neurological abnormalities in Japanese group A xeroderma pigmentosum (XP-A) patients correlates with the sites of non-sense mutation in the XP-A gene. We describe a patient who presented with a more severe photosensitivity and neurological abnormality than those in typical Japanese XP-A patients with a splicing mutation in intron 3. The patient was compound heterozygous for the splicing mutation in intron 3, which resulted in formation of a non-sense codon in exon 4, and a novel non-sense mutation at codon 208 in exon 5, a C to T transition creating a stop codon TAG. Although the combination of these mutations might have been thought to cause only mild neurological signs, the longer truncated XP-A proteins than those of typical XP-A patients may have resulted in severe neurological symptoms. This phenomenon may be explained by a translocation of chromosome (1;10)(q25.3;q22.3) inherited from his father.

In order to determine whether adrenal and gonadal weak androgens are utilized to form active androgens in human hair, we studied the expression of mRNA for androgen receptor (AR), 5alpha-reductase and 17beta-hydroxysteroid dehydrogenase (17beta-HSD) in cultured dermal papilla cells (DPCs) from various body sites. AR mRNA was expressed in beard (Be) and axillary hair (Ax) DPCs from both sexes, but only at a low level in DPCs from occipital scalp hair (OS). Type I 5alpha-reductase mRNA was expressed by all DPCs. Type II 5alpha-reductase mRNA was identified in beard DPCs, but was absent from OS and Ax DPCs. Type II 17beta-HSD mRNA was strongly expressed in outer root sheath cells (ORSCs), while DPCs except for male Ax expressed no type II 17beta-HSD mRNA. In contrast, type III 17beta-HSD mRNA was strongly expressed in Be DPCs and Ax DPCs from both sexes; ORSCs showed a low level of expression. Expression of type III 17beta-HSD mRNA was not regulated by androgen in DPCs. These results suggest that the sensitivity of hairs to androgen is partially controlled by the site-specific expression of AR, 5alpha-reductase and 17beta-HSD in DPCs.

A putative new herpesvirus, designated Kaposi's sarcoma-associated herpesvirus (KSHV) or human herpesvirus-8 (HHV-8) was recently identified in AIDS-related Kaposi's sarcoma. The DNA sequence of the virus is homologous to the gamma-herpesviruses such as herpesvirus Saimiri or Epstein-Barr virus, both of which are tumorigenic, suggesting that this new virus may also be oncogenic. Thus, we determined whether the virus is present in other skin lesions. DNA samples from 118 skin specimens were tested for the HHV-8 sequence by polymerase chain reaction (PCR) and Southern hybridization. The sequences were detected in 13 of 21 samples from Bowen's disease, three of 11 squamous cell carcinomas, three of 11 actinic keratoses, three of seven leucoplakia, one of six from Paget's disease, one of 12 malignant melanoma, one of seven neurofibromas, two of seven chronic dermatites and one of 14 normal skin samples. On sequencing the PCR products, new mutation points were detected. These results suggest that the virus is associated with lesions other than Kaposi's sarcoma and may be more widespread than expected (with a latent level too low to be detected), like the other herpesviruses. Some lesions. e.g. in Bowen's disease or squamous cell carcinoma, may be locally immunosuppressed, allowing the virus to replicate until the copy number is sufficient for detection.

We report a patient with herpetiform pemphigus (HP) who showed reactivity only with pemphigus vulgaris (PV) antigen but not with pemphigus foliaceus (PF) antigen. Direct and indirect immunofluorescence revealed keratinocyte cell surface staining in the lower layers of the epidermis, where desmoglein 3 (Dsg3) is expressed. Immunoblot analysis, using ethylenediamine tetra-acetic acid-separated human epidermal extracts, revealed that the patient's serum recognized only a 130-kDa polypeptide which co-migrated with Dsg3. By antigen-specific immunoadsorption studies, using desmoglein 1 (Dsg1) and Dsg3 recombinant protein produced by baculovirus expression system, immunoreactivity of the patient's serum was completely adsorbed by Dsg3 alone, but not by Dsg1. These results indicate that this HP patient produced only anti-Dsg3 autoantibodies and no other autoantibodies against components of the keratinocyte cell surface. HP could be a variant of PV, in addition to PF, with unique clinical and histological features.

The effects of eicosapentaenoic acid (EPA, 20:5n-3) on the lipid dynamics of cultured epidermal keratinocytes and their expression of cell adhesion molecules were investigated, and were compared with those of arachidonic acid (AA, 20:4n-6). When keratinocytes were treated with 3 micrograms/ml of EPA or AA for 72 h, these compounds were found to be incorporated into the cells. EPA-induced lipid changes were distinguished by a significant increase in the cellular content of n-3 polyunsaturated fatty acids, whereas AA treatment resulted in an increase in the cellular content of n-6 arachidonic acid. These changes in fatty acid composition were accompanied by an increase in cellular membrane fluidity, which was evaluated by the diffusion coefficient, using the method of fluorescence recovery after photobleaching (FRAP) [from 1.77 +/- 0.34 x 10(-8) cm2/s untreated to 2.23 +/- 0.35 x 10(-8) cm2/s EPA-treated (P < 0.001), and 2.16 +/- 0.35 x 10(-8) cm2/s AA-treated (P < 0.001)]. Intercellular adhesion molecule-1 (ICAM-1) was induced on the keratinocyte membrane in the presence of tumour necrosis factor-alpha and interferon-gamma, and pretreatment with EPA or AA further enhanced the expression, almost to an equal degree, as estimated by flow cytometry (P < 0.05). These results indicate that the modulation of ICAM-1 expression does not seem to be EPA-specific, but is presumably a consequence of increased membrane fluidity due to the increased levels of unsaturated fatty acids of both the n-3 and n-6 series in the membrane.

All the reported Japanese patients with group A xeroderma pigmentosum (XP) have two or three mutations at codon 116 in exon 3, codon 228 in exon 6, and the splicing acceptor site of intron 3 of XP group A complementing (XPAC) gene. A homozygote (XP39OS) with a nonsense mutation at codon 228 has less severe neurological abnormalities than patients with the splicing mutation at the acceptor site of intron 3. As homozygotes for the nonsense mutation at codon 116, which truncates a carboxyl-terminal site of XPAC protein at an early part of its zinc-finger domain, have not been reported previously, the possible severity of associated neurological abnormalities was not known. We report a group A XP patient, XP18OS, who had neurological abnormalities which were more severe than those in patients homozygous for the splicing mutation. The polymerase chain reaction product from exon 3 of the patient's XPAC gene was digested completely into three fragments by MseI restriction endonuclease. Thus, the patient was homozygous for the mutation at codon 116.

We describe a technique to facilitate histopathological detection and quantitative measurement of trace amounts of tissue minocycline. In a patient with minocycline-induced hyperpigmentation, a series of biopsies were taken from the affected skin over a period of 54 months, and examined for tissue minocycline deposition. Frozen sections treated with 1 M MgCl2-ethanol yielded minocycline-specific yellowish fluorescence, the location of which corresponded to clumps of granular deposits in the dermis. A decrease in the number of fluorescent granules correlated with the clinical resolution of hyperpigmentation and a significant decrease in the tissue minocycline level. Our data also provide further support for the concept that the pigment granules contain insoluble complexes of minocycline chelated with iron. The fluorescence technique is simple, sensitive, and reproducible.

We report a patient undergoing haemodialysis, who developed multiple subcutaneous nodules. Histology showed that the nodules were composed of deposits of crystals in the dermis, with an associated foreign-body reaction. The crystalline deposits were identified as calcium oxalate by histochemical staining, polarizing microscopy, and analytical electron microscopy.

Histological, immunohistochemical, and ultrastructural studies were performed on two cases of histologically unusual extramammary Paget's disease. Histologically, the central area of the lesions showed a bowenoid pattern, and the peripheral area showed typical extramammary Paget's disease. The transition zone showed an intermediate pattern. All these areas were positive for CEA and EMA, and negative for S-100 protein. Ultrastructurally, in the intermediate pattern, the tumour cells had abundant cytoplasmic glycogen, and the widened intercellular spaces contained numerous glycogen particles, which were probably secreted by the tumour cells. It is well known that eccrine glands, but not apocrine glands, secrete glycogen particles. Therefore, the present findings suggest that some cases of extramammary Paget's disease are a proliferation of germinative cells with eccrine gland differentiation.

The effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) on the growth and DNA synthesis of cultured human keratinocytes obtained from involved and uninvolved psoriatic epidermis and normal epidermis were studied. Treatment with 10(-8) M and 10(-7) M of 1,25(OH)2D3 inhibited cell growth as follows: 58.5 +/- 19.3% and 21.3 +/- 13.6% in normal keratinocytes (n = 6); 43.8 +/- 22.8% and 17.8 +/- 12.3% in psoriatic uninvolved keratinocytes (n = 4); 51.7 +/- 18.2% and 13.2 +/- 6.4% in psoriatic involved keratinocytes (n = 6). Inhibition was virtually complete at 10(-6) M. DNA synthesis was also inhibited by 10(-8) M, 10(-7) M and 10(-6) M of 1,25(OH)2D3 as follows: 70.0 +/- 8.3%, 59.0 +/- 6.8% and 16.7 +/- 4.0%, respectively, in normal keratinocytes (n = 3); 78.5 +/- 13.5%, 51.5 +/- 25.5% and 24.5 +/- 21.5%, respectively, in psoriatic uninvolved keratinocytes (n = 2); and 69.3 +/- 14.5%, 41.3 +/- 19.1% and 14.8 +/- 11.2%, respectively, in psoriatic involved keratinocytes (n = 4). These results indicate that 1,25(OH)2D3 functions as a growth inhibitor for cultured human keratinocytes derived from both normal and psoriatic skin.

Prostaglandins E1 and E2 stimulate cyclic AMP accumulation in pig epidermis and in human epidermis from patients with psoriasis. Prostaglandins A1,A2 and F2alpha are relatively ineffective. The fact that this stimulation is not inhibited by a beta-blocker (propranolol) and that the stimulation by prostaglandin E2 and adrenaline is additive indicates that each drug acts independently on the epidermal adenyl cyclase system. In other words, prostaglandins E1 and E2 act on a site other than the beta-receptor of adenyl cyclase in epidermis. The stimulation by prostaglandins E1 and E2 is not additive; hence they probably act on the same site. Concentrations of prostaglandin E above 3X10(-7) M are effective in causing stimulation. This concentration may be within the physilogical range and the contribution of endogenous prostaglandin levels in the control of intracellular cyclic AMP levels cannot be disregarded.

In order to study the biological and possible pathological roles of cyclic adenosine 3',5'-monophosphate (cyclic AMP) in the skin, it is mandatory to measure cyclic AMP in 50-100 mug of microdissected epidermis, dermis or appendages. In the present study, we offer a method of extracting cyclic AMP from less than 100 mug of tissue, removing contaminating nucleotides and scaling down Gilman's method to fit the analysis of small amounts of tissue. Cyclic AMP levels in the dermis, epidermis, and hair follicles (bulbs) were approximately 1, 2 and 3-5 pmols/mug dry weight tissue respectively. This procedure is applicable to the measurement of cyclic AMP levels in limited foci of healthy or diseased skin.

The cyclic AMP content of epidermal slices is increased by incubation with ethanol, the effect of which is dose-dependent from I to 5% concentration in the incubation media. n-Propanol and acetone are also effective at a concentration equimolar to 5% ethanol. Experimental results suggest that this effect of ethanol is due to activation of adenylate cyclase, rather than to the inactivation of cyclic AMP-phosphodiesterase.

The effect of various hormones and drugs on the adenyl cyclase system of pig and human epidermal slices was studied in vitro. Adrenaline and isoproterenol in the presence of theophylline increased the epidermal cyclic AMP level 20-fold in 5 min. Noradrenaline also stimulated cyclic AMP accumulation but to a much lesser degree. The adrenaline stimulation was marked even in the absence of the phosphodiesterase inhibitor, theophylline. Theophylline potentiated the effect of adrenaline at the concentration of 2-10 mM although theophylline alone did not elevate the cyclic AMP level significantly. The Km for adrenaline stimulation of the adenyl cyclase system of pig epidermis was 7-7 X 10(-7) M. A beta-adrenergic antagonist, propranolol, markedly inhibited the adrenaline stimulation while alpha-antagonists, phentolamine or priscoline, showed little effect. The results are in accord with the view that the epidermis possesses an active adenyl cyclase system with beta-adrenergic receptors.

The cyclic adenosine 3',5'-monophosphate (cyclic AMP) content of pig skin was measured several seconds to minutes after removal of the skin from the body. It increased very rapidly, reached a maximum by 2 min after removal (4 times higher than the initial level), then decreased very slowly. Propranolol injected into the animal before or added after the removal of the skin did not suppress this phenomenon. The practical significance of this finding (increase of cyclic AMP level in skin after ischaemia) is obvious-in order to measure cyclic AMP level in vivo, the sample must be frozen immediately to avoid an 'artificial' increase in cyclic AMP.

A 12-year-old girl, suffering from xeroderma pigmentosum (XP), had mild cutaneous and neurological abnormalities. She showed no neurological abnormalities at the age of seven, but areflexia of the patellar tendons at II. She had no malignant tumours. The skin fibroblasts from the patient were about twice as sensitive to the lethal effects of 254 nm ultraviolet (UV) radiation as those of Group C XP patients, and about twice as resistant as those of typical Group A XP patients. The ability of these fibroblasts to reactivate UV-damage adenovirus 5 was intermediate between those of Group C and typical Group A patients. The patient's cells were assigned to genetic complementation Group A by use of the cell-fusion technique. This is the first case in Japan of a Group A XP patient with mild neurological abnormalities. The mild cutaneous manifestations of this patient may be explained by the residual ability of the cells to repair UV-damaged DNA.

A deficiency of epidermal cyclic adenosine 3', 5'-monophosphate (cyclic AMP) has been implicated as the cause of the incomplete differentiation, increased mitosis and increased glycogen concentration which characterize the psoriatic lesion. This communication contains our data on the epidermal concentration of cyclic AMP in the lesional and 'normal' (non-involved) skin of patients with psoriasis. In these studies we have introduced the following improvement in methodology: (1) Local ischaemia in the biopsy specimens was prevented by not giving any injections prior to removal of the tissues and by freezing the tissues prior to removal. (2) The epidermis was microdissected from the dermis prior to cyclic AMP assay as as to give as pure an epidermal specimen as possible. Epidermal cyclic AMP was found to be 20-25% higher in the skin lesion than in the uninvolved skin when compared on a dry weight or protein basis but essentially when compared on the basis of DNA content. Our conclusion is that the cyclic AMP level in the psoriatic lesion is not lower than that in the 'normal' skin and thus these characteristics in psoriatic lesions cannot be related simply to a cyclic AMP deficiency.

Active forms of vitamin D3, 1 alpha-hydroxyvitamin D3 and 1 alpha,25-dihydroxyvitamin D3, were administered in an open-design study to 40 patients with psoriasis vulgaris in three ways: to 17 patients 1 alpha-hydroxyvitamin D3 was given orally at a dose of 1.0 micrograms/day for 6 months, to four patients 1 alpha,25-dihydroxyvitamin D3 was given orally at a dose of 0.5 microgram/day for 6 months, and 19 patients were given 1 alpha,25-dihydroxyvitamin D3 applied topically at concentration of 0.5 microgram/g of base for 8 weeks. Improvement was observed at the end of the individual study periods in 13 (76%) patients in Group 1 with a mean period of treatment (+/- SD) of 2.7 +/- 0.6 months, in one patient in Group 2 at 3 months after the start of treatment, and in 16 (84%) patients in Group 3 when the chemical was applied for 3.3 +/- 1.2 weeks. No side-effects were observed in any of these trials. These data suggest that psoriasis may respond to active metabolites of vitamin D3 and that abnormalities in vitamin D metabolism or in responsiveness of the skin cells to active metabolites of vitamin D may be involved in the pathogenesis of this skin disease.

A patient on long-term minocycline therapy developed blue-black discoloration on the legs. Skin biopsy specimens from the pigmented areas were examined by light and electron microscopy and energy-dispersive X-ray microanalysis. Pigmented granules were present at all levels of the dermis and subcutaneous fat tissues. Ultrastructural examination showed electron-dense granular material within the cytoplasm of dermal macrophages and energy-dispersive X-ray microanalysis indicated that the granules contained iron. Thyroid tissue obtained by aspiration biopsy showed the presence of fine brown granules within the cytoplasm of the follicular epithelial cells. An extract of skin from the pigmented areas was subjected to high performance liquid chromatography and minocycline was detected.

A conditioned medium from cultured human epidermal cells was observed to inhibit the activity of exogenous urokinase. By reverse fibrin autography after SDS polyacrylamide gel electrophoresis, a plasminogen activator inhibitor was detected with a molecular weight of 46,000. Using Mr 33,000 [125I]-labelled urokinase we observed the formation of an enzyme-ligand complex. The molecular weight of this complex was 79, 000. These results indicate that cultured human epidermal cells secrete a plasminogen activator inhibitor (urokinase inhibitor) with a molecular weight of 46,000.

Thirty cases of X-linked ichthyosis (XLI) and 32 cases of ichthyosis vulgaris (IV) were diagnosed by measuring the steroid sulphatase activity of peripheral blood lymphocytes or the electrophoretic mobility of serum LDL or both. The clinical features of the two conditions were then compared. In both diseases 60-66% of patients had a family history of the condition. Ichthyosis was noted at birth or immediately afterwards in 59% of the patients with XLI while it appeared in infancy in 68% of those with IV. Scales were mostly large and brown or dark brown in patients with XLI, while the majority of patients with IV had small brown or light brown scales. The distribution of the ichthyotic lesions differed in the two types of ichthyosis. On the trunk, the abdomen was more severely involved than the back in 63% of the cases with the XLI, whereas the back was more scaly than the abdomen in 44% of those with IV. On the extremities, the extensor surface was more severely affected than the flexor surface in both types. X-linked ichthyosis was characterized by the presence of lesions in the pre-auricular area, which were found in 93% of the cases with XLI, while only 17% of the IV patients had ichthyotic lesions at this site. Involvement of the preauricular area could be an important clinical feature for distinguishing XLI from IV.

A plasminogen activator (PA), Mr 72,000, was detected in conditioned medium from human melanocyte cultures by fibrin autography. The electrophoretic mobility was identical to that of tissue PA produced by Bowes melanoma cells. PA activity in human melanocyte culture medium was inhibited by anti-tissue PA IgG, but not by anti-urokinase IgG. Our results are the first to show that normal human melanocytes in culture secrete tissue plasminogen activator.

Virological studies were performed on 12 patients with epidermodysplasia verruciformis (EV). Three types of lesions were observed: red plaques, pityriasis versicolor (PV)-like macules and plane warts. Human papillomavirus (HPV) 14, 20 and 21 were isolated from the plaques, HPV 3, 14 and 38 from flat warts and HPV 5, 12, 17, 20 and 38 from PV-like lesions. No clear relationship could be established between the different lesions and the types of HPV. Types 17 and 20 have been isolated most frequently from Japanese EV patients and HPV 5, frequently detected in other countries, is less common, whereas HPV 8 has not been isolated. Skin cancers occurred in six of the cases (50%) and all had benign lesions that were PV-like. At least one type of HPV 5, 17 or 20 could be isolated from these benign lesions and HPV 17 or 20 detected in the cancers. These three types of HPV in EV patients appear to be involved in the malignant transformation.