Humoral immune response to Malassezia furfur in patients with pityriasis versicolor and seborrheic dermatitis

The postmortem stature was measured in 57 Korean adult males (age range: 20-86 years old, mean: 52.3 years old) in supine position. After dissection of the corpses, we measured the maximum length of the remaining limb-bones (humerus, radius, ulna, femur, tibia and fibula). The correlation coefficients between the stature and each limb-bone length were calculated. Simple regression equations for estimating stature from each limb-bone length and multiple regression equations from the combination of limb-bone lengths were also obtained.     

Polymorphism of Malassezia furfur

Alterations in the morphologic and physiologic characters of 11 isolates of Pityrosporum orbiculare were noted upon prolonged maintenance in pure culture. Successive subculturing of each isolate resulted in its progressive conversion from globose (P. orbiculare) through ovoid to cylindrical (P. ovale) form. Globose forms utilized neither olive oil nor Tween 20 as a sole carbon source, nor KNO3 as a sole source of nitrogen, while ovoid and cylindrical forms utilized both of these carbon sources, and one of four strains of the cylindrical form assimilated KNO3. These results suggest that P. orbiculare and P. ovale are stages in the complex developmental cycle of a single species (Malassezia furfur), but the three names should be preserved until the life cycle is more fully understood.     

Colonization of living skin equivalents by Malassezia furfur

In previous studies, we withdrew thyroid hormones by thyroidectomy before, at, or after the onset of photostimulation and showed that male American tree sparrows (Spizella arborea) are programmed for seasonal reproduction and postnuptial molt by or before Week 3 on long days. In this corollary study, we withdrew long days before or after the control circuits had been programmed. After 1 day to 4 wk on long days, groups of thyroid-intact males were returned to short days until Week 7, when they were moved to constant light and evaluated for photosensitivity or photorefractoriness and postnuptial molt. Long-day controls held 7 wk on long days showed robust testicular growth through Week 6 and then spontaneous testicular regression. Testes of short-day controls and of males photostimulated for 1 day remained small. In all other groups, photostimulation induced testicular growth, which gave way to regression during exposure to short days. Long-day controls tested photorefractory at Week 7 and initiated molt by Week 10. All other groups tested photosensitive and did not molt. Our demonstration that long days are required for expression of seasonal reproduction and postnuptial molt in thyroid-intact male tree sparrows previously programmed for these events suggests that long days create a milieu that is permissive for expression.     

In vitro susceptibility of Malassezia furfur to the essential oil of Melaleuca alternifolia

The susceptibility of 64 Malassezia furfur isolates to Melaleuca alternifolia oil was determined. The minimum inhibitory concentration for 90% of isolates was 0.25% by agar dilution and 0.12% by broth dilution. These data indicate that tea tree oil may be useful in the treatment of skin conditions involving M. furfur.     

Biotin recycling impairment in phenylketonuric children with seborrheic dermatitis

OBJECTIVE: To investigate the effect of a therapeutic diet on serum biotin levels and to explain the seborrheic dermatitis in phenylketonuric (PKU) patients on a "loose" diet. DESIGN: Forty-seven patients were divided into two groups: group A (n=21) demonstrated good compliance to a special diet and group B (n=26) were on a "loose" diet. Most of the patients in group B (20/26), who suffered from mild seborrheic dermatitis, were requested to return to phenylalanine (Phe)-restricted diet for at least 15 days. Seventy-nine healthy children of comparable age were used as controls. Biotin serum levels and plasma biotinidase activity were measured in patients as well as controls. In addition, biotinidase activity was evaluated in vitro after incubation with various concentrations of Phe. RESULTS: Biotin levels in group A patients (636+/-118 ng/L) were statistically significantly elevated (P < 0.01) compared with those of group B patients before (412+/-184 ng/L) and after (501+/-160 ng/L) 15 days on a Phe-restricted diet, as well as with those of controls (337+/-290 ng/L). Furthermore, biotinidase activities were decreased in group B patients (4.2+/-1.68 nmol/min/L) compared with those of group A patients (6.4+/-0.7 nmol/min/L) and controls (6.10+/-0.8 nmol/min/L). Additionally, biotinidase activities in the patients of group B were restored to normal (5.78+/-0.81 nmol/min/L), with a simultaneous remission of their skin lesions, after 15 days on a Phe-restricted diet. Moreover, the in vitro findings showed a 51% inhibition of biotinidase activity when incubated with Phe (20 mg/dL). CONCLUSIONS: It is suggested that the high biotin levels in group A patients reflect the intake of water-soluble biotin of vegetable origin. In contrast, the low biotinidase activity in group B patients may be attributed to their high Phe plasma levels, which acts as an enzyme inhibitor, as shown by the in vivo and in vitro results. Consequently, the observed seborrheic dermatitis in PKU children (group B) is associated with an impairment of biotin recycling.     

Demonstration of Malassezia furfur and M. sympodialis together with M. pachydermatis in veterinary specimens

In the present study, 47 wild-type isolates of the genus Malassezia were isolated from dog and cat specimens by means of a simple differentiating system recently published. The purpose was to determine whether any of the other seven Malassezia spp. apart from M. pachydermatis occur in carnivores. Of the 47 isolates, three had been obtained from cats (ear 2, skin 1) and 44 from dogs (ear 37, skin 3, faeces 2, claw and paw 2). After primary isolation, they were subcultured on mDixon agar and then purified and differentiated by means of assimilation of Cremophor EL, splitting of esculin, growth on lipid-free medium and formation of tryptophan-dependent pigments and fluorochromes. Thus, a total of 100 strains could be obtained from the 47 primary isolates. Referring to the source material, M. pachydermatis was found in 83%, M. furfur in 45% and M. sympodialis in 75%. More than 80% of cultures were mixed, comprising two or all three species; a single species was isolated in only nine cases. This shows that animals are not colonized by M. pachydermatis alone, as has been thought until now, but in nearly all cases by mixed cultures. Thus, (domestic) animals could well be a reservoir for other Malassezia species such as M. furfur and M. sympodialis. Surprisingly, Malassezia yeasts were also isolated from dog faeces, indicating that they apparently pass through the gastrointestinal tract in unchanged form after having been taken up by licking colonized areas. The survivability of Malassezia yeasts in highly acid milieu was also demonstrated in vitro. The study confirms the usefulness of the new test procedures and allows new statements concerning the epidemiology of Malassezia yeasts.     

Synthesis of fluorochromes and pigments in Malassezia furfur by use of tryptophan as the single nitrogen source

A new minimal medium consisting only of L-tryptophan (L-Trp) and a lipid source induced formation of brown pigmentation only in the species Malassezia furfur, which diffuses into the agar. Strains of the species M. sympodialis and M. pachydermatis failed to grow on this medium. On mDixon medium, however, after replacement of peptone by L-Trp, growth of all three Malassezia species was achieved. Under these conditions pigment production was observed with all M. furfur strains tested, although the results for M. pachydermatis strains were inconsistent. M. sympodialis strains showed no pigment production. On the minimal medium pigmentogenesis was induced in M. furfur by only 0.01 g% tryptophan; the pH optimum was pH 5. In all M. furfur strains, alternative amino nitrogen sources given concurrently with Trp suppressed pigmentogenesis. Furthermore, there were differences in the optimal temperature among the individual M. furfur strains. CBS 7019, CBS 6000 and CBS 6001 failed to produce pigment at 37 degrees C. The extract of the culture exhibited remarkable fluorescence, and several indole derivatives with a broad spectrum of colours were detected. This finding may have an impact on the clinical appearance of pityriasis versicolor, a very common skin disease caused by lipophilic yeasts of the genus Malassezia. We hypothesize that in pityriasis versicolor metabolic adaptation of Malassezia yeasts to altered nitrogen conditions on superficial skin might be of patho-physiological importance. Tryptophan as an inducer of pigmentogenesis probably accumulates during excessive sweating, a well-known manifestation of pityriasis versicolor.     

Anti-Malassezia furfur antibodies in the population

The authors carried out research into anti-Malassezia precipitating antibodies in the population, specifying the distribution by age and sex. A total of 868 serum specimens from subjects of both sexes, aged between 0 and 80 years, were studied. An immunoelectroprecipitation reaction was used using a M. furfur culture filtrate as antigen. No antibodies were found in children under 11 years, whereas they were present after that age and reached maximum frequency in subjects between 31 and 40 years of age. In subjects up to 50 years of age they were more frequent in women, but in subjects over the age of 50 years they were more frequent in men. Globally, antibodies were found in 31% (270/868) of the subjects examined. The presence of antibodies correlates with data from the literature regarding the isolation of this yeast in relation to age.     

Application of rank analysis of covariance methods to analysis of multiple anatomical regions with treatment for seborrheic dermatitis

This paper presents the advantages of rank analysis of covariance in contrast to the Mantel-Haenszel procedure in the presence of a covariate. In this paper, data from a clinical trial with an indication for seborrheic dermatitis, which afflicts multiple anatomical regions, is presented. This paper presents analysis performed using both the Mantel-Haenszel procedure and rank analysis of covariance for separate anatomical regions, as well as for the combined anatomical regions. The analysis for the combined anatomical regions involves weighted sums over different strata.     

The comparative study of LUMIWARD immunoassay system and CAP RAST system for determination of specific IgE antibody against mite in infantile atopic dermatitis

The neuromuscular blocking effects and the reversibility of cisatracurium 0.1 or 0.15 mg.kg-1 were compared with those of atracurium 0.5 mg.kg-1 during anaesthesia with propofol, nitrous oxide and isoflurane. Neuromuscular block was monitored using train-of-four stimulation while recording the mechanomyographic response of the adductor pollicis muscle. The block was either allowed to recover spontaneously or was antagonised with neostigmine 50 micrograms.kg-1 at 10% or 25% recovery of the first twitch of the train-of-four. The median times to maximum block were 2.7, 2.2 and 1.5 min following cisatracurium 0.1 and 0.15 mg.kg-1 and atracurium 0.5 mg.kg-1, respectively. After cisatracurium 0.1 mg.kg-1 had been given, the median time to recovery of the train-of-four ratio to 0.8 ('adequate recovery') was 74 min during spontaneous recovery, 48 min after reversal with neostigmine when the first twitch of the train-of-four had returned to 10% of control and 50 min after reversal when the first twitch of the train-of-four had returned to 25% of control. These times for cisatracurium 0.15 mg.kg-1 and atracurium 0.5 mg.kg-1 were 90, 66 and 57 min and 75, 56 and 54 min, respectively. Administration of neostigmine significantly shortened the time to adequate recovery for both drugs but there were no significant differences in the case of either neuromuscular blocking drug between the groups of patients given neostigmine at 10 or 25% recovery of the first twitch of the train-of-four.     

Polidocanol sensitivity--a possible tool in the differentiation of Malassezia spp

In recent years, the genus Malassezia was reclassified based on molecular data; in addition to M. furfur, M. pachydermatis and M. sympodialis, four new species (M. globosa, M. obtusa, M. restricta, M. slooffiae) were described. Primary keys for routine identification have recently been presented. Polidocanol was shown to have specific inhibitory effects against Malassezia spp. In an agar diffusion test, type strains of all Malassezia species were incubated with polidocanol concentrations between 0.01% and 10%. M. furfur strains were most resistant, with minimal inhibitory concentrations (MIC) ranging from 7.5% to 10%. Inhibitory concentrations of the other strains were lower by at least one factor of ten. Most sensitive were strains of M. pachydermatis (0.05%). In a further test, polidocanol-containing olive oil was used to determine the sensitivity of Malassezia furfur and M. sympodialis. Again, the inhibitory concentrations for strains of M. sympodialis were one tenth of those found for M. furfur. In addition to its antifungal effects, polidocanol might therefore be a useful tool in differentiating Malassezia species.