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The HLA-DO molecule is a non-classical class II heterodimer composed of alpha and beta chains. We have previously recognized that all eight of the allelic variations of the HLA-DOA gene represent non-synonymous amino acid substitution. In the present study, to analyze genetic polymorphism and allelic variation of the HLA-DOB gene which may affect the efficiency of class II restricted antigen presentation thereby being involved in the susceptibility of HLA associated diseases, we conducted direct DNA sequencing of HLA-DOB in 36 HLA class II homozygous typing cells and identified six new allelic variations (DOB*0101101, *0101102, *01012, *01022, *0104101 and *0104102) including five single nucleotide polymorphisms with only one amino acid substitution. Furthermore, strong linkage disequilibrium was detected between DOB*01022 and DRB1*1502 only, with no linkage disequilibrium between the DOA and the DOB genes. The HLA-DOB gene has been identified in other mammals, and their nucleotide sequences are well conserved. These facts suggest that limited polymorphism in the DOB gene is profitable to execute their unique function as a co chaperone and so strong selective pressure is operating to prevent generic variation against the DOB molecule interacting with the DM molecule and thus maintaining the specified immunological function of regulating antigen presentation.

The Japanese Study Group of Insulin Therapy for Childhood and Adolescent Diabetes (JSGIT) was established in July 1994 with the chief aim to improve the quality of therapy for type 1 diabetes in children, an entity far less common in Japan than in Europe. We proposed four initial research topics: (i) to determine the current status of medical care and glycemic control in Japanese children with type 1 diabetes mellitus; (ii) to standardize the measurement of hemoglobin A1c; (iii) to establish a registry of a large cohort of patients in order to enable prospective studies to improve the quality of therapy for children with type 1 diabetes in Japan; and (iv) to enable participants of the JSGIT to hold a workshop twice annually. We registered a total of 736 patients from 45 hospitals throughout Japan. Intervention via insulin treatment was instituted after 2 yr for those patients whose hemoglobin A1c level was more than 8.1%. The proportion of patients receiving multiple insulin injections increased after intervention; however, average hemoglobin A1c in females remained significantly higher than in males. We identified two forms of diabetes in Japanese children: a rapidly progressive form and a more slowly progressive form. There was a significantly higher prevalence of a family history of diabetes in first-degree relatives in the slowly progressive form. These preliminary findings are the result of the first collaborative study of childhood diabetes in Japan.

Background: The Beutler enzyme spot test is an effective assay for newborn mass screening of galactosemia, but it is qualitative and relies on visual interpretation. We describe a quantitative, instrumental modification of the assay. Methods: We modified the macroscopic visual Beutler enzyme spot test by adding extraction of blood components from filter paper, deproteinization with acetone-methanol, and quantification and recording by a fluorescent microplate reader and personal computer. All handling was performed in microplates. The measurement time was 90 min. Results: Fluorescence intensity (FI) of healthy controls correlated with hematocrit and galactose-1-phosphate uridyltransferase (GALT) activity. Patients with GALT deficiency were distinguished clearly from healthy subjects and heterozygous carriers by FI. FI decreased to 75% of the initial activity after storage at 25 °C for 3 days and to 40% after storage at 37 °C for 7 days. Screening of 46 742 newborns yielded 1 false-positive result (in a heterozygous carrier), 1 patient with glucose-6-phosphate dehydrogenase deficiency, and no apparent false negatives as judged by concurrent measurements of galactose and galactose-1-phosphate. Conclusions: The quantitative Beutler test can provide precise GALT activity in newborn mass screening, and can take into consideration the influence of high temperature and humidity, duration between sampling and testing, and anemia. This method is clinically useful, simple, automated, and highly reliable for newborn mass screening of galactosemia.

Galactokinase (GALK) deficiency is an autosomal recessive disorder, which causes cataract formation in children not maintained on a lactose-free diet. We characterized the human GALK gene by screening a Japanese genomic DNA phage library, and found that several nucleotides in the 5′-untranslated region and introns 1, 2, and 5 in our GALK genomic analysis differed from published data. A 20-bp tandem repeat was found in three places in intron 5, which were considered insertion sequences. We identified five novel mutations in seven unrelated Japanese patients with GALK deficiency. There were three missense mutations and two deletions. All three missense mutations (R256W, T344M, and G349S) occurred at CpG dinucleotides, and the T344M and G349S mutations occurred in the conserved region. The three missense mutations led to a drastic reduction in GALK activity when individual mutant cDNAs were expressed in a mammalian cell system. These findings indicated that these missense mutations caused GALK deficiency. The two deletions, of 410delG and 509–510delGT, occurred at the nucleotide repeats GGGGGG and GTGTGT, respectively, and resulted in in-frame nonsense codons at amino acids 163 and 201. These mutations arose by slipped strand mispairing. All five mutations occurred at hot spots in the CpG dinucleotide for missense mutations and in short direct repeats for deletions. These five mutations in Japanese have not yet been identified in Caucasians. We speculate that the origin of GALK mutations in Japanese is different from that in Caucasians.

Neopterin and biopterin concentrations were measured in cerebrospinal fluid (CSF) and urine samples from controls less than 1 year old. This is the first time for CSF reference data for controls less than 1 year old to be reported. The ratio of neopterin to biopterin in CSF 0-30 days (n = 48) of age in control samples was 0.65 +/- 0.31 (SD), which was far lower than that in urine over the same time period, 4.0 +/- 1.9 (SD), (n = 51). This finding is very important when diagnosing 6-pyruvoyltetrahydropterin synthase (PTPS) deficiency and peripheral form of PTPS deficiency in the neonatal period. Our CSF reference data for controls should be useful in the diagnosis of PTPS deficiency.

The HLA-DO molecule, a heterodimer consisting of two novel members of the class II gene family, DOA and DOB, has recently been suggested to function as an important modulator in the HLA class II restricted antigen presentation pathway by interaction with the HLA-DM molecule. In this study, we have analyzed genetic polymorphism and allelic variation of the HLA-DOA gene in 37 HLA class II homozygous typing cells using the direct DNA sequencing technique. As a result, we recognized at least eight allelic variations, DOA*01011, *0101201, *0101202, *0101203, *01013, *0101401, *0101402 and *01015. None of them, however, result in amino acid substitution. The HLA-DOA gene has been identified in other mammals as well, and the nucleotide sequences were well conserved among these species. These results suggest that the DOA molecule has undergone strong selective pressure to preserve functional structure and conformation required for interaction with the DM molecule, preventing non-synonymous amino acid substituiton Note.

Two novel mutations of the beta-hexosaminidase alpha subunit gene were identified in Japanese patients with the infantile form of Tay-Sachs disease. One mutation was a one-base deletion at nt613C, which generated a stop codon at two codons downstream, in three unrelated patients. The other mutation was a one-base substitution of G-to-A at IVS 5, +1, which caused a splicing abnormality, in one patient. A missense mutation of R170W, which has already been reported in other ethnic groups, was also newly identified in one patient. In 1993, the most common mutation (IVS 5, -1G--T) in Japanese patients with Tay-Sachs disease was reported as the major mutation in Japan accounting for 80% of 56 mutant alleles from 28 unrelated patients. The deletion of nt613C was the second most common mutation, accounting for 5% of the mutant alleles. The previously reported mutation IVS 5, -1G--T and the nt613C deletion found in this study together accounted for 85% of the mutations causing Tay-Sachs disease among Japanese. Since these two mutations were located in or close to exon 6 and since they abolish Fok I (IVS 5, -1G--T) and Sfa NI (nt613C deletion) restriction sites, respectively, they were screened rapidly by single polymerase chain reaction followed by digestion with these enzymes.

Glycogen storage disease type Ib (GSD-Ib) is an inborn error of metabolism with autosomal recessive inheritance, caused by defects in microsomal transport of glucose-6-phosphate. Recently, Gerin et al isolated a human cDNA encoding a putative transporter homologous to bacterial transporters of hexose-6-phosphate, and identified two mutations in its gene in two patients with GSD-Ib (9). Independently, a linkage analysis mapped the GSD-Ib gene on chromosome 11q23 (10). It remains to be elucidated whether the two genes are identical or GSD-Ib is genetically heterogeneous. We first mapped the transporter gene on chromosome 11 by using a DNA panel of human/hamster hybridoma cells. The result suggested that the GSD-Ib genes identified by the two distinct approaches may be identical and GSD-Ib was allelic. We then studied four unrelated Japanese families with GSD-Ib, and found three novel mutations: a four-base deletion/two-base insertion, a point mutation within a consensus splicing donor site, and a missense mutation (W118R). The W118R mutation was found in 4 out of 8 mutant alleles, suggesting that it is prevalent among Japanese patients.

The serologically defined HLA-DR53 antigen is associated with HLA-DR4, -DR7, and -DR9 antigens, and these haplotypes contain two functional genes, DRB1 and DRB4, and two pseudogenes, DRB7 and DRB8. The DRB4 gene encodes the DR53 antigen, and has been officially recognized to contain three allelic variants (DRB4*0101, 0102, and 0103). In this study, we have established the polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) method for DRB4 genotyping and analyzed genetic polymorphism of the DRB4 gene in Japanese population. DRB4*0101, DRB4*0102, and DRB4*0103 could be observed at the frequencies of 0.5%, 1.1% and 32.7%, respectively. The same DRB1 allele does not necessarily share an identical DRB4 allele. Further, a tight linkage disequilibrium was found between DRB4*0I02 and DRB1*0401 in Japanese population, whereas DRB1*0401 was associated with DRB4*0101 or *0103 in Caucasian population. These findings reveal extensive diversity of the HLA-DRB1 and -DRB4 haplotypes and may have important implications for HLA-disease associations and donor selection in unrelated transplantation.

In the HLA-D region, one of the class II genes, DMA and DMB have been identified between the DQ and DP genes, and four allelic polymorphisms in each of the DMA (DMA*0101 approximately 0104) and DMB (DMB*0101 approximately 0104) genes have been so far recognized. Several recent studies suggested that the DM molecule is required for class II antigen presentation pathway especially by promoting the binding of antigenic peptides to the classical HLA class II molecule. In this study, we have analyzed genetic polymorphism and allelic variation of the DMB gene in a Japanese population by the direct DNA sequencing technique and also by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, and could recognize DMB*0101 (49.3%), DMB*0102 (23.2%), DMB*0103 (23.2%), and DMB*0104 (0.4%). Further, a new DMB allele, DMB*0105 characterized by the presence of Val and Ile at two polymorphic sites, codons 144 and 179, respectively was identified. Strong linkage disequilibria were found between DMB*0101 and DRB1*0101, DPB1*0402 and DRB1*1502, and also between DMB*0103 and DRB1*1501 and DQB1*0602. HLA-DMB genotyping using the PCR-RFLP method established here will provide accurate evaluation of the effects of sequence allelism in the DMB gene on the HLA class II disease associations.

We determined the prevalence of antibodies to glutamic acid decarboxylase (anti-GAD) in Japanese diabetic patients. Anti-GAD were detected by RIP Anti-GAD Hoechst, which is a new sensitive radioimmunoassay (RIA) kit using purified pig brain GAD as the antigen. One thousand nine hundred Japanese patients were collected by the Study Group for Antibodies to GAD. The prevalence of anti-GAD in the subjects of this study was: 35.4% (326/921) in all patients with IDDM, 50.3% (96/191) in patients with IDDM less than 1-year duration, 4.3% (29/680) in NIDDM, 37.9% (39/103) in slowly progressive IDDM, 10.5% (4/38) in gestational diabetes mellitus, 0% (0/27) in impaired glucose tolerance, 4.8% (6/124) in the school children with glycosuria, 2.1% (1/47) in the relatives of IDDM and 5.0% (1/20) in neurological diseases without diabetes. The prevalence in normal subjects was 2.2% (7/323). Anti-GAD are frequently detected by the RIA kit in patients with IDDM of short duration and this assay may be useful for population screening for IDDM and for better understanding of its pathogenesis.

The influence of glycemic control on growth and on the development of complications in diabetic children was studied. The subjects of the study were 107 children with insulin-dependent diabetes mellitus (IDDM), who were enrolled in a Summer camp program for diabetic children in Kinki District, Japan from 1972 to 1990, and who had at least three determinations of HbA1 during the observation period. Many of the children had high mean levels of HbA1, regardless of age. The height and weight were below the standards for the respective ages in many children, indicating the retardation of growth. However, S.D. scores for height and weight and other physical indices were not related to the mean levels of HbA1. By contrast, the prevalence of diabetic retinopathy was related to an elevated mean level of HbA1, but that of albuminuria was not. Serum cholesterol levels were higher in children with higher mean levels of HbA1, but serum triglycerides appeared not to be related to glycemic control. The incidence of retinopathy during the observation period closely related to the degree of the mean levels of HbA1, but that of albuminuria did not.

Limb lengthening was performed on a patient with achondroplasia. The first operation was performed without growth hormone (GH) therapy, and the second operation was performed with GH therapy. The effect of GH on limb lengthening was studied. For the lengthening of limbs, the Orthofix device was used on the femur, and the Ilizarov method was used on the tibia. It took more time for the consolidation of the callus and severe narrowing of the femur was observed at the second limb lengthening. GH treatment was of no benefit for the consolidation of the callus in this patient.

1972年から1990年までの近畿小児糖尿病キャンプ参加者で, 3回以上HbA1値を測定した18歳未満のもの107名 (男児43名, 女児64名) について, コントロール状態と発育および合併症との関係について検討した。平均HbA1値は高値を示すものが多い, 年齢による差はみられなかった。発育状況は, 身長, 体重とも標準値を下回るものが多く, また身長, 体重のSD scoreも負領域で, 発育の遅延が示唆された。しかし, 平均HbA1値と身長, 体重のSD score, Kaup指数, Rohrer指数, PDWとの関係はみられなかった。糖尿病性網膜症の合併率は平均HbA1値が高くなるとともに有意に上昇した。しかし, タンパク尿はコントロールとは関係がなかった。一方, 血清コレステロ ール値は, 平均HbA1値が高くなるほど有意に上昇したが, 血清中性脂肪値との関係はみられなかった。観察期間中の新たな糖尿病性網膜症の発生率はコントロ一ル状態の悪い群ほど高く, その差は有意であった。

The mechanism of action of steroid hormones on skeletal growth is not understood in detail. We examined the interactions of steroid hormones and insulin-like growth factor-I (IGF-I) during DNA and sulfated proteoglycan synthesis in rabbit costal chondrocytes. Progesterone at 0.05 nM stimulated the incorporation of [3H]thymidine into DNA by 30% above the control level in confluent cultures, but neither testosterone nor 17 beta-estradiol stimulated DNA synthesis. None of the hormones affected [3H]thymidine incorporation stimulated by IGF-I when chondrocytes were incubated with one of the hormones and IGF-I simultaneously. In contrast, when confluent cultures were incubated with one of the sex steroids for 24 h before the addition of IGF-I, stimulation of DNA synthesis by the growth factor was enhanced about 45% above the control value by 0.5 nM progesterone, 50% by 0.5 nM testosterone, and 80% by 50 nM 17 beta-estradiol. The effects of IGF-I on proteoglycan synthesis, as judged by the incorporation of [35S]sulfate, were stimulated by treatment with progesterone or testosterone. Dexamethasone at physiological concentrations inhibited chondrocyte DNA synthesis in confluent cultures to 10% of the control level. At 50 nM, dexamethasone suppressed IGF-I induction of DNA synthesis by 60%. This suppression was greater when dexamethasone was added before IGF-I than when the additions were simultaneous. When chondrocytes were treated with hydrocortisone or dexamethasone for 24 h before the addition of IGF-I, the glucocorticoids synergistically accelerated proteoglycan synthesis mediated by IGF-I. These findings suggest that steroid hormones have priming effects on the biological action of IGF-I in cartilage metabolism.

There has been no consistent view about the cross-species reactivity of islet cell antibodies (ICA), and no report about their target antigens in the pancreatic islet cells of different species. Therefore, we examined the cross-reactivity of human ICA against rodent pancreatic islet cells, and found at least two types of ICA, one having a comparatively strong cross-reactivity and the other lacking it. Furthermore, using human as well as some rodent pancreatic tissues that had been modified chemically, we came to suspect that the target antigens of ICA were sialic acid residues of glycolipids. Therefore, we suggest that there are at least two types of ICA recognizing sialic acid residues of glycolipids, one reacting with antigen(s) commonly present in human and rat islets, and the other with antigen(s) only present in human islets.

HLA is an important etiologic genetic factor in Type I diabetes and specific HLA-class II genes are closely related to the onset of the disease. Many differences in the patterns of susceptible and resistant DRB1, DQA1, and DQB1 genes have been observed among various ethnic groups. We have previously shown that DRB1*0405, DRB1*0901 and DQA1*0301-DQB1*0302 were the major susceptible alleles or haplotype to Type I diabetes while DR-DQ haplotype studies suggested the important role of DR and DQ alleles in susceptibility and resistance in Japanese patients. Based on the analysis of 90 Japanese patients with childhood onset Type I diabetes and 136 unrelated healthy Japanese controls by polymerase chain reaction-restriction fragment polymorphism method (PCR-RFLP), we report here the association of Type I diabetes with DPB1*0201 (relative risk = 2.29; Pc = 0.027) in this population. Comparison of linkage disequilibrium patterns between patients and controls showed that the significantly high prevalence of DPB1*0201 among patients cannot be attributed simply to linkage disequilibrium with susceptible DRB1 alleles and DQA1-DQB1 haplotypes. Our results suggest that in addition to alleles at the DRB1, DQA1, DQB1 loci, polymorphism at DPB1 locus also influences the risk of Type I diabetes.

We identified 14 mutations in 15 Japanese subjects from 13 families with galactose-1-phosphate uridyltransferase (GALT) deficiency using denaturing gradient gel electrophoresis (DGGE) and direct sequence analysis. These mutations accounted for 22 (96%) of 23 mutant alleles in 15 Japanese subjects. The mutational spectrum included nine missense mutations (M142V, G179D, A199T, R231H, W249R, N314D, P325L, R333Q, and R333W), two deletions (L275fsdelT and Q317fsdelC), a nonsense mutation (W249X), and two splicing mutations (V85-N97fsdel38bp and IVS4nt+1). Ten of the 14 mutations have not been reported in Caucasians. Differences in frequency and spectrum of GALT mutations suggest that the mutations may have occurred after racial divergence of Caucasians and Asians. The Duarte variant in Japanese was associated with the N314D mutation, g.1105GC, g.1323GA, and g.1391GA (SacI -) polymorphisms, as in Caucasians. The Duarte variant may have occurred before racial divergence, and was an ancient mutation. In vitro GALT activities of nine missense mutations were determined by a COS cell expression system, and indicated between 1.3% and 35% of wild-type control. Patients with R333Q (29% in vitro GALT activity) or A199T (35%) showed mild clinical phenotypes, i.e. no ovarian failure or neurological deterioration. Genotype determination is useful for predicting biochemical and clinical phenotypes in classic galactosaemia, and can be of further help in managing patients with this disorder.

We identified three mutations in four Japanese patients with central type 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency. One missense mutation was a C-to-T transition, resulting in the substitution of Pro by Ser at codon 87 (P87S) in exon 5. Another missense mutation was a G-to-A transition, resulting in the substitution of Asp by Asn at codon 96 (D96N) in exon 5. A splicing mutation was found by skipping of exon 4 on PTPS mRNA analysis, and a G-to-A transition at the third base of codon 81 (E81E) and at the terminal base in exon 4 were detected on genomic PTPS DNA analysis. The E81E mutation affected the splice donor site of exon 4 and caused the splicing error. In COS cell expression analysis, the P87S and D96N mutant constructs revealed, respectively, 52% and 10% of wild-type activity. Patients with P87S/P87S (52%/52% in-vitro PTPS activity) exhibited 0.11 and 0 microU/g hemoglobin [Hb] in erythrocyte PTPS activity (wild-type control: 11-29 microU/gHb) erythrocyte PTPS activity, and the patient with P87S/D96N mutations (52%/10%) had 0.97 microU/gHb in PTPS erythrocyte activity. The PTPS erythrocyte activity did not coincide with the in-vitro PTPS activity based on patient genotype.

It is not clear yet when pancreatic islet cells begin to express antigens for islet cell antibodies (ICA). Therefore, we studied whether human ICA-positive sera, crossreacting with adult rat islet cells, react with fetal and neonatal rat islet cells immunohistologically. The ICA did not react with fetal islet cells. On the other hand, neonatal islet cells over 2-3 weeks of age expressed the reactivities almost similar to those of the adult. It was suspected that pancreatic islet cells started to express their antigens to induce ICA gradually after birth.

We characterized phenylalanine hydroxylase (PAH) genotypes of Japanese patients with phenylketonuria (PKU) and hyperphenylalaninemia (HPA). PKU and HPA mutations in 41 Japanese patients were identified by denaturing gradient gel electrophoresis and direct sequencing, followed by restriction fragment length polymorphism analysis to find a large deletion involving exons 5 and 6. Of 82 mutant alleles, 76 (92%) were genotyped showing 21 mutations. The major mutations were R413P (30.5%), R243Q (7.3%), R241 C (7.3%), IVS4nt-1 (7.3%), T2781 (7.3%), E6nt-96A-->g (6.1%), Y356X (4.9%), R111X (3.7%), and 442-706delE5/6 (2.4%). Eight new mutations (L52 S, delS70, S70P, Y77X, IVS3nt-1, A132 V, W187 C, and C265Y) and a polymorphism of IVS10nt-14 were detected. In vitro PAH activities of mutant PAH cDNA constructs were determined by a COS cell expression system. Six mutations, viz., R408Q, L52 S, R241 C, S70P, V388 M, and R243Q, had 55%, 27%, 25%, 20%, 16% and 10% of the in vitro PAH activity of normal constructs, respectively. The mean pretreatment phenylalanine concentration (0.83+/-0.21 mmol/l) of patients carrying the R408Q, R241 C, or L52 S mutation and a null mutation was significantly lower (P

Four unrelated Japanese patients with infantile Sandhoff disease (beta-hexosaminidase beta-subunit deficiency) have been studied for the molecular basis of their severe phenotype. Two patients had complex base substitutions; one patient was homoallelic for a triple mutation (P417L, K121R, and S255R) and the other was a compound heterozygote of a double (P417L and K121R) mutation and the triple mutation. K121R is known to be a functional polymorphism, while P417L (exon 11, +8 C--T) generates predominantly an abnormally spliced mRNA at base +112 of exon 11 and has been described in two patients with a juvenile form of the disease. The mild phenotype is attributed to the presence of a small amount of normally spliced mRNA. S255R is a novel mutation without prior description in the literature. An expression study of the normally spliced cDNA with the double and the triple mutations gave about 70% and 30% of normal activity, respectively. This finding suggests that S255R further reduces the catalytic activity of the already below-threshold amount of normally spliced mRNA and accounts for the more severe phenotype in our patients. In the other two patients, a novel disease-causing base transition was found within intron 10, away from the intron/exon junction (-17 a--g). This mutation caused abnormal 3' splicing at position -37 of intron 10, and no normally spliced product was detectable upon RT-PCR analysis. We noted an unusually low splice site score (61.8) for the exon 10/intron 11 junction and suspected that this might be partially responsible for the aberrant splicing in these mutations. To test this hypothesis, we constructed four chimeric cDNAs all with an additional intron 10 inserted and evaluated their splicing efficiency. They, respectively, had the normal sequence, P417L (exon 11, +8 C--T), the intronic mutation (-17 a--g), and the intronic mutation with an artificially engineered intron 10/exon 11 junction of a higher splice site score (85.1). Of the total transcripts, 67% and 32% were correctly spliced in the normal chimeric construct and P417L, respectively, while no normally spliced product was generated either in the chimeric construct with -17 a--g or in that with a high splice site score. The sequence around the adenosine -17 residue upstream of the normal acceptor splice site in this report, UGCAAU (-21 to -16), matches the consensus branchpoint sequence YNYRAY (Y, pyrimidine; R, purine; N, any base) reported in the literature. The mutation in this study is most likely to abolish lariat formation because the artificial site of the high splice site score did not improve splicing efficiency.

An outbreak of Escherichia coli O157:H7 infection occurred in July 1996 in Sakai City. About 5000 children were infected, 122 of whom developed hemolytic uremic syndrome (HUS). In this outbreak, almost all patients were administrated some type of antibiotics. The effects of antibiotics on E. coli O157 associated hemorrhagic colitis (HC) have been controversial. In this study, we focused on the effects of antibiotics on development of HUS in the HUS in the Sakai outbreak. We retrospectively determined the antibiotics administrated within three days after the onset of HC, clinical courses, and laboratory data of 301 patients who were hospitalized and identified as Escherichia coli O157 infection by stool culture, from results of questionnaires sent by the Osaka Prefecture Medical Association to hospitals in Osaka Prefecture. The antibiotics used could be identified for 216 patients. The incidence of HUS among these patients was 11.6%. They were divided into 19 groups based on the type of antibiotics administrated. The incidence of HUS in the new quinolone (3.7%) group was low, but was high in the intravenous cephalosporin (18.2%) group. The differences in the incidence of HUS among the 19 antibiotic groups was significant (p < 0.05) on analysis of covariance which eliminated the contributions of variables including age, sex and laboratory data. These findings indicate that the suitable antibiotics can prevent the development of E. coli O157-associated HUS.

The present study was carried out to elucidate whether renal hemodynamic changes are associated with angiotensin converting enzyme (ACE) gene polymorphism in patients with insulin dependent diabetes mellitus (IDDM). We studied 32 Japanese patients with IDDM (aged 15 +/- 3 years in mean +/- SD) without renal failure or retinopathy. Renal hemodynamics were examined by duplex Doppler sonography and arterial resistance index was calculated. ACE genotypes were determined by polymerase chain reaction amplification. Resistance index (RI) of arcuate arteries in IDDM patients with DD genotype was significantly elevated, being 0.64 +/- 0.04, 0.66 +/- 0.05, and 0.71 +/- 0.05 for II, ID and DD genotype groups, respectively (II vs. DD, p0.02). In patients with DD genotype with normoalbuminuria (n = 27), it was also significantly elevated in DD genotype patients (II vs. DD, p0.02). In addition, multiple regression analysis with a forward elimination procedure showed that only the ACE genotype was associated with RI of arcuate arteries (R2 = 0.24, p0.01) among the parameters of sex, age, IDDM duration, body mass index, HbA1c, plasma glucose levels, serum levels of total cholesterol and creatinine, urinary albumin excretion index, mean blood pressure and ACE genotype. The present study demonstrated that renal arterial resistance is elevated in IDDM patients with DD genotype. ACE gene polymorphism which could be linked to intrarenal circulatory disturbance may be associated with the initiation and progression of diabetic nephropathy.

Succinyl-CoA:3-ketoacid CoA-transferase (SCOT; EC 2.8.3.5) deficiency (McKusick 245050) is a rare inherited metabolic disease. This enzyme is a key enzyme for utilization in peripheral tissues of ketone bodies that are produced by the liver. The absence of SCOT activity blocks peripheral ketone body utilization and causes recurrent attacks of severe ketoacidosis beginning in the neonatal or infantile period. Five cases of SCOT deficiency have been reported (Tildon and Cornblath 1972; Spence et al 1973; Middleton et al 1987; Saudubray et al 1987; Perez-Cerda et al 1992). The prognosis of these patients seems to parallel the severity of the SCOT deficiency. Here we report a new case of SCOT deficiency in Japan. We also report SCOT activity in the lymphocytes of the patient and his family.

We characterized two novel mutations of the galactose-1-phosphate uridyltransferase (GALT) gene intwo Japanese patients with GALT deficiency and identified N314D and R333W mutations, previouslyfound in Caucasians. One novel missense mutation was an G-to-A transition in exon 8, resulting in thesubstitution of arginine by histidine at the codon 231 (R231H). GALT activity of the R231H mutantconstruct was reduced to 15% of normal controls in a COS cell expression system. The other was asplicing mutation, an A-to-G transition at the 38th nucleotide in exon 3 (318AG), resulting in a38-bp deletion in the GALT cDNA by activating a cryptic splice acceptor site. In seven Japanesefamilies (14 alleles for classic form and one allele for Duarte variant) with GALT deficiency, the R231H and 318AG mutations were found only on both alleles of the proband. The N314D and R333W mutations were found on one allele each. The Q188R was prevalent in the United States butnot in Japanese patients. The N314D mutation was associated with the Duarte variant in Japanesepersons, as well as in the United States. We speculate that classic galactosemia mutations appear todiffer between Japanese and Caucasian patients. Our limited data set on galactosemia mutations in Japanese suggests that the N314D GALT mutation encoding the Duarte variant arose before Asianand Caucasian people diverged and that classic galactosemia mutations arose and/or accumulated afterthe divergence of Asian and Caucasian populations. © 1995 Wiley-Liss, Inc.

More girls with phenylketonuria (PKU) enter childbearing ages, and most such women are mentally normal, having been born since newborn screening was initiated in the 1970s and treated from early infancy with a low phenylalanine (Phe) diet. Women with PKU not treated prior to conception can have a pregnancy that results in serious fetal damage1. Maternal PKU as a cause of mental retardation and birth defects is a new phenomenon. There will be an increased need for specific therapies in maternal PKU. Low Phe diet is essential for the treatment of maternal PKU. It should be started before pregnancy and it is necessary to maintain their plasma Phe levels around 5 mg/dl throughout their pregnancy2. However they are usually controlled around 10 mg/dl because of the difficulty of the diet therapy. We made an animal model of maternal PKU by the intravenous injection of Phe to pregnant guinea-pigs, and examined plasma, liver and brain Phe levels in their fetuses after an intravenous administration of 6R-5,6,7,8-tetrahydrobiopterin (R-BH4) to the mothers.

Tetrahydrobiopterin (BH4) synthase deficiency has a high incidence of low birth weight,1 and some of them had a mild mental retardation in spite of their early treatment2. In this study we performed an intravenous loading of 2,4-diamino-6-hydroxypyrimidine (DAHP) with a small amount of BHU, and successfully made a model of fetal BH4 deficiency. We investigated the possibility of the fetal therapy of BH4 deficiency in this model by measurements of phenylalanine(Phe), tyrosine(Tyr), BH4, dopamine and catecholamines.

Tetrahydrobiopterin (BH4) has been used for the therapy of BH4-deficient patients. However, BH4 is poorly absorbed from the intestine. The plasma level of biopterin that was reached after oral administration of BH4 to a BH4-deficient patient was reported to be 1–2% of the levels reached after either intravenous or subcutaneous administration1. This poor absorption from the intestine needs a large amount of BH4 for the oral therapy, leading to high costs.

The frequency and distribution of eight mutations (R111X, IVS4nt-1, Y204C, R243Q, IVS7nt-2, W326X, Y356X, and R413P) in the phenylalanine hydroxylase gene of Orientals in Japan and Korea were examined by allele-specific oligonucleotide hybridization. The mutant alleles comprised 54 and 55% of the phenylketonuria (PKU) chromosomes examined in 36 patients in Japan and 10 patients in Korea, respectively. The spectrum of PKU mutations in Japan was similar to that in China, particularly in northern China, but different from that in Korea. The IVS4nt-1 mutation had a high frequency in Korea and southern China, due to the result of the founder effect and genetic drift. The R413P mutation, which may have originated in the regions surrounding the Baikal, expanded to northern China and Japan. We did not find Caucasian mutations in the Japanese or Korean PKU chromosomes. Thus, PKU mutations occurred after racial divergence between Caucasians and Mongoloids, and there were different founding populations for PKU in the two populations.

Purpose: Several noniiivasive imaging methods can detect epileptic ioci. We compared tnagnetic source imaging (MSI) of epilcptic spikes with the results of other imaging mcthoda, including positron emission tomography (PET), single photon emission CT (SPECT), and MRI, in order to determine characteristics of each. Methods: We studied 9 patients, age ranging from 1–23 years. Etiologies included acute encephalopathy, tubcrous sclerosis, pcrisylvian syndrome, and cerebral infarct in I patient each, unknown in the rest. Eight exhibited bca/ization-related epilepsy (LRE) and the remaining iut syndrome (LGS). Informed cnsent was obtained from the patients or their parents. Thc magnctocncephalograins (MEG) were measured in 21 magnetically shielded room using a layingtype whole-cortex MEG with 160-channel first-order gradiometers. We estimated the equivalent current dipoles (ECD) of spikes in the simultaneously recorded EEG. MRI scanning was performed at 5 m m thickness in 3 directions including the markers for superimposition with MEG. IXF-FDG PET was performed with a Headtome IV in 4 paticnts and 123Tc ECD SPECT with a Toshiba GCA9300 in 8 patients. We visually evaluated these images. Results: We could estimate the ECD in 8 patients as having I or multiple locations. All 4 patients examined by PET cxhibitcd 1 or more hypometabolic arcas on PET. SPECT studies revealed hypoperfusion areas in 3 patients m d hyperperfusion areas in 2 patients. One id the patients with hypcrpcrfusion was on ictal study. Structural ahnormalities were presented on MRI in 3 patients. Casc I had advcrsivc seizures with turning to the lcft and exhibited a broad right frontotemporal hypometabolic area on PET. Her ECDs wcrc cstimatcd to originate from the right prcmotor area, in agreement with a hypoperfusion spot on ictal SPECT. Case 2 had epilepsy as a residuum of past cnccphalopathy and had complcx partial seizures (CPS) with rapid generalim tion. The foci detected on MSI, PET, and SPECT did not agree. Casc3 had CPS and anterotemporal hypomctabolism on PET. ECDs were focused in the lateral mterotemporal area. Case 4 had tuberous xlc- rosis and a past history of status cpilcpticus. MRI revealed cortical tubers and white matter lesions. Cortical tubers exhibited hypoperlu- sion on SPECT. However, ECDs werc cstimatcd to originate from the right occipital hypoperfusion area and not thc cortical tubcrs. C was suspected to have idiopathic LRE and exhibited no focus on PET and SPECT. ECDs were estimated to originate from the left frontal cortex. Case 6 had pcrisylvian syndrome with LGS. Bilaterally abnormal cortex exhibited hyperperfusion on SPECT, and ECDs wcrc citimated to originate lrom this cortex. Casc 7 had CPS and left temporal sporadic spikes on previous EEGs. The findings of SPECT and PET studies were normal, and ECDs could not be estimated because there was no spike in the MEG study. Case 8 had right leg pain and frontal slow wave bursts on the EEG. PET rcvcaled right frontal and left parietal hypometabolism, and ECDs were estimated to originate from the left parietal area. Case 9 had an old inraretion in the lcft occipital lobe and CPS. SPECT revealed perfusion defect in the infarction and right frontal hypoperfusion. ECDs were estimated to originatc from the margin of the infrarction. Conclusions: Interictal MEG studics can dctcct irritable zones of epileptic foci, hut their findings sometimes do not accurately reveal the epileptogcnic zone. However the majority of our cstimatcd ECDs agreed with the ictal symptomatology and the foci detected by PET and SPECT. The estimated area of ECDs was usually smaller than hypometabolic areas on PET and hypoperfusion area on SPECT. Multimodal interictal studies with noninvasive technologics will enablc more enable detection of epileptic foci.

The activities of 14 lysosomal enzymes in chorionic villi at gestational ages of 6-12 weeks were assayed. Arylsulphatases A and B, alpha-glucosidase and beta-glucuronidase activities increased with advancing gestational age. When compared with the activity in cultured amniotic fluid cells, arylsulphatase A, beta-galactosidase, alpha-glucosidase, heparan N-sulphatase, alpha-L-iduronidase, alpha-mannosidase, neuraminidase, and sphingomyelinase showed significant differences. All except beta-glucuronidase showed lower activity in chorionic villi than in cultured amniotic fluid cells. Prenatal diagnosis using chorionic villi was possible except for alpha-L-iduronidase. Storage at -20 degrees C up to 42 days did not significantly affect activity. The results emphasize the importance of using fresh or frozen age-matched control tissue for diagnosis.

OBJECTIVE To determine whether hemodynamic changes in retinal arteries precede clinical manifestations of diabetic retinopathy and to examine the effects of control of hyperglycemia on retinal artery blood flow. RESEARCH DESIGN AND METHODS We assessed blood flow in bilateral central retinal arteries in 50 insulin-dependent diabetes mellitus (IDDM) patients without retinopathy and 20 sex- and age-matched control subjects using duplex Doppler sonography. We determined the peak systolic velocity (PSV), end-diastolic velocity (EDV), time-averaged velocity (TAV), resistance index (RI), and pulsatility index (PI). RESULTS PSV, EDV, and TAV were significantly lower in IDDM patients than in control subjects (P < 0.05, P < 0.01, and P < 0.01, respectively). The RI was significantly higher in IDDM patients than in control subjects (P < 0.01) and was significantly correlated with plasma levels of glucose in IDDM patients (r = 0.0.310, P = 0.0248). Multiple regression analysis identified the plasma levels of glucose as a significant determination of RI in IDDM patients. After 14 days of intensive insulin therapy in 7 IDDM patients, the RI and plasma levels of glucose showed significant decreases (P = 0.018, P = 0.001, respectively). CONCLUSIONS Our results showed that changes in retinal hemodynamics were present before the clinical detection of overt diabetic retinopathy and suggest that the presence of short-term hyperglycemia partly contributes to impaired retinal circulation.

Serum immunoglobulin (IgG, A, M) levels were measured in 123 children with Type I diabetes in order to clarify the relationship between immunoglobulin levels and islet cell antibodies (ICA) or the duration of illness and to investigate the incidence of selective IgA deficiency in children with Type I diabetes in Japan.IgA levels in Type I childhood diabetics were significantly higher than in normal children; however, IgG and IgM levels in Type I childhood diabetics were similar to those in normal children. There was no correlation between immunoglobulin (IgG, A, M) levels and the duration of illness. Immunoglobulin levels in patients with ICA were about the same in those without ICA. IgM levels in ICA-positive patients with a duration of less than one year were significantly higher in ICA-negative patients. Two out of 123 children (1.6%) with Type I diabetes had selective IgA deficiency.From these results, it was suggested that high IgM levels in ICA-positive diabetic children with short duration might show recent viral infection and that the incidence of IgA deficiency in Japanese children with Type I diabetes was slightly lower than in Caucasians.

In order to prevent vertical transmission of hepatitis B virus (HBV), yeast recombinant HB vaccine at a dose of either 5 mcg or 10 mcg was administered to 185 infants born to mothers who were positive for HBs antigen (HBsAg). All of them developed antibody to HBsAg (anti-HBs) after three vaccinations. Generally, the cutaff index (COI) of anti-HBs by radioimmunoassay (RIA) was higher in the 10 mcg dosage group than in the 5 mcg dosage group. The geometric mean titer (GMT) of anti-HBs, as measured by quantitative RIA, in the former group was 2.4 times that in the latter one month after the third vaccination. The incidence of clinical reactions was only 4% in a total of 561 injections, and none of the reactiom were severe. It is conduded that recombinant HB vaccine is safe and has excellent immunogenicity for infants requiring prevention of HBV vertical transmission. It is also suggested that 10 mcg doses of the recombinant HB vaccine can provide more solid protection to high-risk infants without serious adverse reactions. (Acta Paediutr Jpn 1989; 31: 180–185)

In a nationwide cross-sectional study of Japanese type-1 diabetics, whose disease had manifested itself before the age of 18, we found (1) the long-term outcome of childhood diabetes to be very poor, (2) the prevalence of microvascular complications to be stronly related to the age of the patients and the duration of diabetes, and (3) the prevalence of retinopathy to be dependent on the degree of diabetic control. Of 90 diabetics born before 1955, 7 had died, 71 had retinopathy of which 36 were proliferative, 47 had cataracts, 12 were blind, 44 had nephropathy, 42 had neuropathy, and 18 had hypertension. Retinopathy was present in 1.8% under the age of 12, in 8.3% from the age of 13 to 16, in 22.1% between the age of 17 to 20, and in 52.5% over the age of 20. A comparison between age-matched subgroups with and without retinopathy showed that the percentages of patients who were cooperative, with good control and without hyperlipidemia were higher in the group having no retinopathy than in the other.