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T Arinami

Publications and source records attributed to T Arinami.

125 records · Page 7Linked to original sources

Possible Werner syndrome. A unique association with spontaneous digital gangrene in infancy and decreased life span of cultured skin fibroblasts.

BACKGROUND: Werner syndrome is a hereditary disease characterized by several features generally associated with aging. However, the differences between Werner syndrome and the normal aging process are clear. Werner syndrome is usually diagnosed through the clinical signs and symptoms it presents. In recent years, however, the cultured skin fibroblasts of patients have grown slowly and patients have a short life span; these characteristics provide a useful diagnostic aid. OBSERVATIONS: We recently examined a 42-year-old single man who had short fingers, marked facial scars resulting from chilblain-like eruption in infancy, glaucoma caused by uveitis developed in his middle age, callosities on the soles, and immaturation of sexual glands. Repeated peripheral blood examinations showed a positive result for antinuclear factor, slight elevation of immunoglobulin levels, and a low leukocyte count. His family had repeated consanguineous marriages and his parents were cousins. We cultured skin fibroblasts from the patient's forearm and compared them with those of four normal control male subjects. The patient's skin fibroblasts showed a remarkably low population growth rate and a total replicative life span. CONCLUSION: The patients presented unique clinical features for Werner syndrome such as chilblain-like eruption in infancy and glaucoma caused by uveitis. Cell culture studies revealed cellular abnormalities compatible with Werner syndrome. We thus diagnosed the patients as possibly having Werner syndrome.

Adult↗

A case of trisomy 21 with holoprosencephaly: the fifth case.

A case of trisomy 21 with holoprosencephaly, the fifth case in the literature, is described. The patient also had extracephalic malformations frequently associated with Down syndrome. The possibility of a causal relationship between trisomy 21 and holoprosencephaly is discussed.

Abnormalities, Multiple↗

Chromosomal assignments of the human endothelin family genes: the endothelin-1 gene (EDN1) to 6p23-p24, the endothelin-2 gene (EDN2) to 1p34, and the endothelin-3 gene (EDN3) to 20q13.2-q13.3.

Chromosomal assignments of the genes for the human endothelin family, the endothelin-1 gene (EDN1), the endothelin-2 gene (EDN2), and the endothelin-3 gene (EDN3), were accomplished by in situ hybridization to human metaphase chromosomes using a 3H-labeled human preproendothelin cDNA probe for each endothelin. The chromosomal assignment of the EDN2 was also performed by Southern blot analysis of somatic cell hybrid DNAs. EDN1, EDN2, and EDN3 were mapped to 6p23-p24, 1p34, and 20q13.2-q13.3, respectively.

Chromosome Banding↗

Neuropsychiatric disturbances in a patient with a nonmosaic isodicentric (X) (q21.32) chromosome.

A 41-year-old female patient with mental retardation and generalized epileptic seizure had a nonmosaic idic (X) (pter-q21.32::q21.32-pter) chromosome in peripheral lymphocytes and bone marrow cells. Primary amenorrhea, myelodysplastic syndrome, pigmented nevi and characteristic facial appearance were also observed. A few cases with the nonmosaic idic (X) (q::q) with various breakpoints reported previously commonly showed ovarian failure with dysfunction of relevant hormone. CNS abnormalities of the present case were demonstrated by CT, MRI and SPECT using 123I-IMP. CNS abnormalities were considered to be possibly due to karyotype with a nonmosaic idic (X) (q21.32).

Abnormalities, Multiple↗

Replication patterns of the fragile X in heterozygous carriers: analysis by a BrdUrd antibody method.

The replication status of the fragile X chromosomes was studied in short-term cultures of lymphocytes from six female heterozygous carriers. The fragile X was induced by adding 0.1 microM fluorodeoxyuridine during the last 24 h of culturing. The replication status of the X chromosomes was studied using a bromodeoxyuridine (BrdUrd) antibody method. BrdUrd was added (1) at a final concentration of 0.2 micrograms/ml during the early S phase of chromosome replication (16-10 h before harvest), (2) at 0.2 microgram/ml during the late S phase (the last 6 h of culturing), (3) at 20 micrograms/ml during the early S phase, and (4) at 20 micrograms/ml during the late S phase. BrdUrd that was incorporated into replicating chromosomes was detected by using a nuclease and BrdUrd monoclonal antibody. The frequency of the fragile X was reduced by BrdUrd treatment. The degree of reduction was more severe in the 20 micrograms/ml than in the 0.2 microgram/ml series and was more severe with late S than with early S treatment. Of the early- and late-replicating fragile X chromosomes, those which were actively replicating during a BrdUrd treatment were more reduced than the others. Thus, the average rate of early and late S treatment with 0.2 microgram BrdUrd/ml was assumed to be the closest reflection of the situation in vivo. There was no correlation between the average rate of the early replicating, active fragile X and the intelligence of the heterozygous carriers studied.

Adolescent↗

Auditory brain-stem responses in the fragile X syndrome.

Auditory brain-stem responses (ABRs) were recorded from a group of 12 mentally retarded males with the fragile X (fra[X]). The responses were analyzed in terms of ABR thresholds, absolute latencies, and interpeak latencies. One patient had increased ABR thresholds, indicating hearing impairment. Five fra(X) subjects had prolonged I-V interpeak latencies. Comparisons between the fra(X) group (excluding one possible hard-of-hearing subject) and a control group of age-matched males with normal intelligence showed that the fra(X) group's interpeak latencies were significantly prolonged for the III-V and I-V but not for the I-III. This pattern of prolongation of interpeak latencies suggests that central, as opposed to peripheral, nervous-system dysfunction predominates in many patients having this syndrome. In addition, frequently observed prolongation of the transmission time may indicate that brain-stem white-matter functioning is also apt to be involved in this syndrome.

Adolescent↗

Frequency of the fragile X syndrome in institutionalized mentally retarded females in Japan.

The fragile X [fra(X)] syndrome was screened on 190 Japanese institutionalized females with moderate to severe mental retardation. Two inmates with severe mental retardation (IQ 20) had the fra(X) chromosome in 26% and 15% of the cells examined, indicating that the prevalence of the fra(X) syndrome was about 1% in all female inmates and was about 3.27% in severely mentally retarded females without known causes. However, no female with fra(X) syndrome was found in 35 moderately retarded females. Both had brothers with the fra(X) syndrome and the prevalence was 10% in females with a family history of mental retardation. In addition, the replication study of the fra(X) chromosome in the patients supported the proposal that an excess of the early replicated fra(X) chromosome is related to the mental capacity in heterozygous females. Therefore, the fra(X) syndrome should not be ignored even in severely mentally retarded females with a family history, though the heterozygotes are commonly normal to subnormal in their mental development. In addition, the replication study of the fra(X) chromosome may help to estimate mental development in the carrier children.

Adolescent↗

A fragile X female with Down syndrome.

Clinical and cytogenetic aspects of a female infant with trisomy 21 and the fragile X [fra(X)] chromosome are reported. Most of the facial characteristics of the patient are those observed in Down syndrome, but some features such as long face with prominent forehead and lower jaw, and large ears are related to the fra(X) syndrome. The origin of an additional chromosome 21 may be ascribed to maternal first meiotic nondisjunction in our case. It has been suspected that female carriers of the fra(X) chromosome may be predisposed to meiotic nondisjunctional events. However, there is probably no relationship between the two chromosomal abnormalities in our case because of the maternal age at the delivery.

Adult↗

Frequency of the fragile X syndrome in Japanese mentally retarded males.

Among 243 institutionalized mentally retarded males in Japan, 13 patients (5.3%) with the fra(X)(q27) from nine families were detected. These 13 patients accounted for 8.6% of 152 male inmates with unknown causes of mental retardation in the population. One out of nine pedigrees had an apparently unaffected male transmitter of this disorder. Our data agree with the frequencies of the fra(X) syndrome in various retarded populations, most of which were Caucasians, suggesting that the prevalence of the fra(X) syndrome in Japanese is not significantly different from those in Caucasians.

Adolescent↗

Relationship between age and IQ among fragile X males: a multicenter study.

Longitudinal decline in IQ among fragile X males was reported recently. However, there are problems in retesting IQ that may affect scores. Two such factors are intertest time interval and score obtained on the first test. To determine the generality of IQ score changes, we examined 101 fragile X males from 6 centers. To ensure high test-retest reliability, only results from Stanford-Binet and Wechsler tests were used. Thus there were retest scores from 60 subjects. Test-retest reliability between first and last scores was very good (r = 0.85) and comparable to those seen in nonfragile X mentally retarded individuals. Also computed were z-scores of differences in IQ scores. The z-score differences were distributed about a mean at 1 SD below the expected zero value. Eighteen subjects showed statistically significant decreases in IQ, 6 showed statistically significant increases, while 5 showed the same scores. Z-score differences were not correlated with type of residence or elapsed intertest interval, but were negatively correlated with first score obtained, indicating a regression-to-the-mean effect. Using a multiple regression analysis, we found first score obtained, age tested, and age retested significant predictors of score differences, accounting for 19% of the total variance. These results suggest that factors previously identified as affecting retest scores have a smaller effect than originally thought. It is suspected that decline in IQ is associated with dynamic neurological processes and needs to be investigated further.

Adolescent↗

Longitudinal changes in IQ among fragile X males: clinical evidence of more than one mutation?

Longitudinal changes in IQ among mentally retarded (MR) fragile X [fra(x)] males have been reported previously. While age is associated with decline in IQ, not all males are so affected. This suggests that there may be more than one subtype of affected fra(X) male. Therefore, we examined the distribution of standardized difference scores (Zdiff) in IQ to determine if subjects were from an admixture of at least 2 populations. Cluster analysis of Zdiff scores was used to partition subjects into 2 groups. Goodness-of-fit tests indicated that scores were more likely to come from an admixture. Discriminant functions (DF) were calculated to determine predictive validity of Zdiff scores. To eliminate the effect of skewing, a power transform was applied to Zdiff scores and DFs recomputed. Zdiff and transformed scores provided similar results. The mean and variance for one group showed no differences in test-retest scores as would be expected from examining any population while the mean for the second group indicated significant decline in IQ nearly 4 standard errors below the first test score. These results suggest that there may be clinical evidence for 2 types of fra(X) mutation: One which causes MR but is static, and a second mutation which causes MR but is dynamic and contributes to an apparent longitudinal decline in cognitive function.

Adolescent↗

Methylation analysis of the fragile X syndrome by PCR.

The fragile X syndrome is predominantly caused by a large expansion of a CGG trinucleotide repeat in the promoter region of the FMR1 gene, which is associated with methylation and downregulation of transcription. The molecular diagnosis of this disorder is based on repeat size and methylation analysis of the FMR1 gene usually by Southern blot analysis. We describe a PCR-based method for the analysis of methylation of the FMR1 gene, which involves bisulfite treatment of DNA prior to amplification. Fifty-two normal and 48 affected, premutation, or mosaic males were analyzed in a blinded study by this method. A prospective study of 30 males suspected of fragile X was also performed. Amplification specific for the methylated FMR1 sequence was readily observed in all individuals with a full mutation, whereas all normal and premutation individuals showed only amplification-specific for the unmethylated sequence, thus, allowing affected and unaffected males to be distinguished. A full mutation in the presence of mosaicism was also detectable by this method. Methylation-specific PCR appears to be a rapid and reliable tool for the diagnosis of fragile X males.

Base Sequence↗

No evidence for an association between a variant of the mast cell chymase gene and atopic dermatitis based on case-control and haplotype-relative-risk analyses.

Atopic dermatitis (AD) is a chronic relapsing dermatitis which belongs to the group of atopy-related diseases as well as asthma and allergic rhinitis. As a probable genetic risk which may contribute to the organ specificity of AD, an association between AD and a genetic variant of the gene encoding mast cell chymase (MCC), which has chymotrypsin-like specificity and is abundant in skin mast cells, has been reported in a Japanese population. We tried to confirm the role of this polymorphism in the development of AD in a Japanese population. A case-control analysis using 100 AD patients and 101 controls did not show a significant difference in the frequency of the BB genotype between the patient and control groups (odds ratio 1. 12, p = 0.81). The haplotype relative-risk analysis using 69 patient-parents trios did not suggest an association (chi2 = 0.177, p = 0.92). Thus, we failed to confirm the association between the polymorphism in the MCC gene and AD in the Japanese population.

Adult↗