A rare variant in CYP27A1 and its association with atopic dermatitis with high serum total IgE.

This study investigated rare variants associated with atopic dermatitis. We performed exome analyses on 37 patients who were diagnosed with atopic dermatitis by board-certified dermatologists and had total serum IgE levels greater than 1000 IU/ml. The exome analysis identified seven variants with <1% allele frequency in Asian (ASN) population of 1000 Genomes Project phase 1 data and >5% allele frequency in the atopic dermatitis exome samples. We then conducted a replication study using 469 atopic dermatitis patients with total serum IgE ≥1000 IU/ml and 935 Japanese controls to assess the presence of these 7 candidate variants. The replication study confirmed that CYP27A1 rs199691576 (A/G) was associated with atopic dermatitis with high serum IgE levels (P = 0.012, odds ratio = 2.1). CYP27A1 is involved in the metabolism of vitamin D3, which plays important roles in modulating immune function. Previous studies have reported polymorphisms in vitamin D pathway genes that are associated with allergy-related phenotypes. Our data confirm the importance of genes regulating the vitamin D pathway in the development of atopic dermatitis.

Decreased fidelity in replicating DNA methylation patterns in cancer cells leads to dense methylation of a CpG island.

Cancer cells that have a large number of aberrantly methylated CpG islands (CGIs) are known to have CpG island methylator phenotype (CIMP), and decreased fidelity in replicating methylation patters has been analyzed as an underlying mechanism. First we developed a method to analyze the number of errors in replicating CpG methylation patterns in a defined period. A single cell was expanded into 106 cells, and the number of errors during the culture was measured by counting the deviation from the original methylation patterns. It was shown that methylated status of a CpG site was more stably inherited than unmethylated status, suggesting that the genome is constantly exposed to de novo methylation. Promoter CGIs showed higher fidelities than CGIs outside promoter regions. We then analyzed error rates in two gastric cancer cell lines without CIMP and two with CIMP for five promoter CGIs. Two CIMP(-) cell lines showed error rates smaller than 1.0x10(-3) errors per site per generation (99.90%-100% fidelity) for all the five CGIs. In contrast, AGS cells showed significantly elevated error rates, mainly due to increased de novo methylation, in three CGIs (1.6- to 3.2-fold), and KATOIII cells showed a significantly elevated error rate in one CGI (2.2-fold). Presence of densely methylated DNA molecules was observed only in KATOIII and AGS. These data demonstrated that some cancer cells have decreased fidelity in replicating CpG methylation patterns that underlie CIMP.

[Gel-type agar color dosimeter].

Gel-type color dosimeter which is made by dissolving 2 kinds of dye in agar is developed. The dosimeter has following characteristics. (1) The dosimeter is easy to make and can be formed easily to any shape required. (2) The dose and dose distribution in krad region can be measured by color change of the dosimeter. (3) The 3 dimensional dose distribution can be observed by cutting or slicing the irradiated dosimeter. The dosimeter is used in the sprout inhibition experiment of potato by electron irradiation. From the data obtained, several irradiation conditions of the irradiating machine and irradiation method can be decided most suitably.

[Inspection of inner structure of sealed 60Co sources by the autoradiography with radcolor film].

In studies using 60Co gamma-ray irradiation, an extremely high dose rate is often required and samples must be placed very near a 60Co source. The dose rate in the vicinity of the source depends on the inner structure of the source. Therefore, it is necessary to examine the distribution of source activity. As a method of the examination an autoradiographic technique using several coloring materials for irradiation was tried. The materials used were "Radcolor film" developed by our center, besides a glass, polymethylmethacrylate (PMMA) and a blue cellophane. Results showed that the autoradiography with Radcolor film is very useful to examine the position, the size and the activity difference of 60Co pieces by the change of color.

Hereditary complement (C9) deficiency associated with dermatomyositis.

A 28-year-old Japanese woman with hereditary complement (C9) deficiency and dermatomyositis is reported. She had a 3-year history of facial erythema and a 1-month history of progressive muscle weakness. Clinical and laboratory findings were suggestive of dermatomyositis; muscle biopsy confirmed an inflammatory myopathy. An unexpected finding, however, was the low titre of serum haemolytic complement (CH50). Treatment with prednisolone resulted in marked clinical improvement but did not affect the CH50 titre. Further investigation revealed a selective and total absence of the ninth complement component (C9), with direct DNA sequence analysis revealing a non-sense mutation at Arg95 of the C9 gene. This case demonstrates that the muscle lesions of dermatomyositis can occur in the presence of a complement defect that would prevent the formation of the C5b-9 membrane attack complex.

Immunoenzymatic assay of anti-diphtheric toxin antibodies in human serum.

An enzyme-linked immunosorbent assay was developed for measuring immunoglobulin G anti-diphtheric toxin antibodies in human serum. The assay was done in plastic plates coated with purified diphtheric toxoid. Since a straight-line relationship was found between logs of extinction values and of antibody concentrations, with a very constant slope, serum titers could be expressed as log10 of the serum dilution corresponding to a definite optical density, such as 0.5. The assay furnished highly reproducible titers on a continuous range, with coefficients of variation less than 10%. Only one or two serum dilutions were usually sufficient for serum titration. To establish correspondence of the enzyme-linked immunosorbent assay titers with biologically determined antitoxin international units, a regression equation was fitted between the respective values for 112 serum samples titrated in both tests. The enzyme-linked immunosorbent assay titer of 2.38 corresponded to an antitoxin titer of 0.01 U, which is considered as the minimal protective level. Simple to perform, economical, and precise, the immunoenzymatic assay seems to be a very practical procedure for seroepidemiological purposes.

Quantificacao de anticorpos diftericos em cobaias. I. Persistencia do titulo de anticorpos sericos em animais inoculados com uma dose de toxoide difterico. / Qualification of diphtheria antibodies in guinea pigs. I. Persistence of serum antibodies level in animals inoculated with a dose of diphtheria toxoid

Foi estudado o comportamento da cinetica de anticorpogenese em cobaias inoculadas com uma dose de toxoide difterico precipitado pelo alumen. Paralelamente, foi estudada a dinamica da imunidade passiva naturalmente transmitida aos filhotes. Em cobaias vacinadas com uma dose de antigeno, foi verificado que a sintese de antitoxina difterica persiste, em titulos detectaveis, ate 36 meses apos. Os anticorpos transferidos, passivamente, da mae vacinada para os filhotes atingiram nestes,concentracoes plasmaticas superiores, sendo que a imunidade perdurou em titulos detectaveis ate cerca de tres meses de idade dos mesmos