GATA3 abnormalities and the phenotypic spectrum of HDR syndrome

We report on GATA3 analysis and the phenotypic spectrum in nine Japanese families with the HDR syndrome (hypoparathyroidism, sensorineural deafness, and renal dysplasia) (MIM 146255). Fluorescence in situ hybridisation and microsatellite analyses showed heterozygous gross deletions including GATA3 in four families. Sequence analysis showed heterozygous novel mutations in three families: a missense mutation within the first zinc finger domain at exon 4 (T823A, W275R), an unusual mutation at exon 4 (900insAA plus 901insCCT or C901AACCCT) resulting in a premature stop at codon 357 with loss of the second zinc finger domain, and a nonsense mutation at exon 6 (C1099T, R367X). No GATA3 abnormalities were identified in the remaining two families. The triad of HDR syndrome was variably manifested by patients with GATA3 abnormalities. The results suggest that HDR syndrome is primarily caused by GATA3 haploinsufficiency and is associated with a wide phenotypic spectrum.

Hypospadias and the androgen receptor gene: mutation screening and CAG repeat length analysis

We report on mutation screening and CAG repeat length analysis of the androgen receptor (AR) gene in 21 patients with hypospadias. The urethral meatus was located at the glandular region in six patients (glandular type), at the penile shaft in seven patients (penile type), and at the scrotal/perineal region in eight patients (scrotal/perineal type). Mutation screening was performed for exons 1-8 and their flanking introns (except for the CAG and GGC repeat regions at exon 1) by the heteroduplex detection method and showed no abnormal chromatograms. The CAG repeat length analysis was carried out using 50 normal boys and 50 fertile males as controls, and demonstrated no statistically significant difference in the median of CAG repeat lengths or in the frequency of long CAG repeats (> or = 26 or > or = 28) between the controls and the patients with the three different types of hypospadias. The results suggest that AR gene abnormalities do not constitute a major factor in the development of hypospadias.

Superoxide scavenging activities of sixty Chinese medicines determined by an ESR spin-trapping method using electrogenerated superoxide

Superoxide-scavenging activities of 60 kinds of Chinese herbal medicines were determined accurately by an electron spin resonance (ESR) spin-trapping technique using 5,5-dimethyl-1-pyrroline 1-oxide (DMPO) as a spin-trapping reagent. As a source of superoxide in this method, superoxide generated by one-electron reduction of the oxygen molecule in dimethyl sulfoxide solution was used. As a result of these studies, very powerful scavenging activity was found in Chinese medicines for inflammation, diseases of blood circulation and for tumors.

ESR imaging on a solid-tumor-bearing mouse using spin-labeled dextran

Imaging of a tumor with ESR was tried using two different types of spin probes, a low molecular weight spin probe, CPROXYL, and a polymer spin probe, TEMPO-DX. Spin probes were administered to a mouse bearing a solid tumor that was a transplanted Ehrlich's ascites carcinoma in the back, using two methods, conventional intraperitoneal injection and continuous intravenous injection with a micro-feeder. First, the accumulation of the probe was examined by X-band ESR. CPROXYL, which was administered to a mouse intraperitoneally, was exclusively retained in urine, showing that it was rapidly excreted into the bladder, while TEMPO-DX was absorbed from the peritoneal cavity with difficulty to the vessel. Using continuous intravenous injection, CPROXYL was also rapidly excreted, but it was confirmed that TEMPO-DX concentrated in tumor tissue because it has a long half-life in vivo. In addition, measurement of ESR imaging was done to measure the distribution of spin probes with continuous intravenous injection. The strongest spot of CPROXYL was observed on ESR images, showing the accumulation at the bladder, while the spot of TEMPO-DX was observed in the solid tumor of the back of the mouse. These results suggest that TEMPO-DX could stay much longer than a low molecular weight spin probe in vivo and concentrate at the tumor. TEMPO-DX may be useful for developing specific ESR imaging agents for tumor.

[A case of free-floating ball thrombus in left atrium with mitral stenosis]

We report a rare case of free-floating ball thrombus in the left atrium with mitral stenosis. The patient was 71-year-old woman who admitted to the local hospital for transient ischemic attack. Electrocardiography showed atrial fibrillation and an echocardiogram examination revealed free-floating ball thrombus in the left atrium with mitral stenosis. She was transferred to our hospital for emergency open heart operation. After removal of the ball thrombus, mitral valve replacement and modified MAZE procedure were successfully performed. The size of the ball thrombus was 40 x 30 x 33 mm and weighed 20 g. Postoperative course was uneventful.

47,XXX male: A clinical and molecular study

We report a 53-year-old Japanese male with a 47,XXX karyotype. His clinical features included hypoplastic scrotal testes (4 ml bilaterally), normally formed small penis (3.8 cm), relatively poor pubic hair development (Tanner stage 3), gynecomastia, age-appropriate male height (159.1 cm), and mental retardation (verbal IQ of 56). Serum testosterone was markedly reduced (0.6 nmol/L). A needle biopsy showed severe testicular degeneration. FISH analysis revealed complex mosaicism consisting of (1) 47,XXX cells with a single copy of SRY (n = 177), two copies of SRY (n = 3), and no SRY (n = 1); (2) 46,XX cells with a single copy of SRY (n = 9) and no SRY (n = 3); (3) 45,X cells with no SRY (n = 5); and (4) 48,XXXX cells with a single copy of SRY (n = 1) and two copies of SRY (n = 1). PCR analysis showed the presence of Yp portion with the breakpoint between DYS264 and AMELY. Microsatellite analysis demonstrated three alleles for DMD and AR. X-inactivation analysis for the methylation status of the AR gene showed random inactivation of the three X chromosomes. The results suggest that this 47,XXX male has resulted from abnormal X-Y interchange during paternal meiosis and X-X nondisjunction during maternal meiosis. Complex mosaicism may be due to the age-related increase in mitotic nondisjunction which is prone to occur in rapidly dividing lymphocytes and to the presence of two randomly inactivated X chromosomes which may behave asynchronously during mitosis, and clinical features of this male would primarily be explained by the genetic information on the SRY (+) der(X) chromosome and his advanced age.

SHOX haploinsufficiency and overdosage: impact of gonadal function status

Since its discovery in 1997, knowledge about the SHOX gene has rapidly increased. In this review, we summarise clinical features and diagnostic and therapeutic implications in SHOX haploinsufficiency and overdosage. SHOX haploinsufficiency usually results in mesomelic short stature and Turner skeletal features, including Madelung deformity with puberty, in subjects with normal gonadal function. Thus, identification of early or mild signs of Madelung deformity is pivotal for the diagnosis, and gonadal suppression therapy may serve to mitigate the clinical features. By contrast, SHOX overdosage usually leads to long limbs and tall stature resulting from continued growth into the late teens in subjects with gonadal dysgenesis. Thus, the combination of tall stature and poor pubertal development is the key to diagnosis, and oestrogen therapy can help the prevention of unfavourably tall stature as well as the induction of sexual development. These findings, in conjunction with skeletal assessment in Turner syndrome and expression analysis during human embryogenesis, imply that SHOX functions as a repressor for growth plate fusion and skeletal maturation in the distal limbs and, thus, counteracts the skeletal maturing effects of oestrogens.

In vivo ESR study on hepatic reduction of a nitroxide radical after administration of glucose in rats

The in vivo reducing ability of a nitroxide radical, 4-hydroxyl-2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPOL), in the liver of rats was estimated by using an electron spin resonance spectrometer equipped with a surface-coil-type resonator following administration of glucose. Both oral and intravenous administration of glucose significantly enhanced the reduction capacity. In vitro studies show that the reduction site of TEMPOL in the hepatic homogenate is located in the mitochondrial respiratory chain and microsomal electron transport system. These findings indicate that the enhancement of activity of these systems caused by the glucose administration prompts reduction of TEMPOL in the liver.

Inducible expression of basic transcription factor-binding protein 2 (BTEB2), a member of zinc finger family of transcription factors, in cardiac allograft vascular disease

BACKGROUND

We have recently identified basic transcription factor-binding protein 2 (BTEB2), which is involved in phenotypic modulation of vascular vascular smooth muscle cells. The aim of this study was to investigate the expression of BTEB2 in cardiac allograft vascular disease.

METHODS

Heterotopic cardiac transplantation was performed in rats. All grafts were stained with antibodies against for BTEB2 and cyclin-dependent kinase 4 for immunohistochemical study. The intensity of BTEB2 expression was also calculated.

RESULTS

In the allografts at 4 and 8 weeks after transplantation, smooth muscle cells were positive for BTEB2 in the diffusely thickened coronary arteries and the perivascular space. BTEB2 expression was closely associated with cyclin-dependent kinase 4 expression. The BTEB2 expression score was significantly higher in the allografts compared with the isografts.

CONCLUSIONS

The induced expression of BTEB2 may play a potential role in the development of the cardiac allograft vascular disease.

Genetic evidence for a novel gene(s) involved in urogenital development on 10q26

BACKGROUND

Although the frequent association between distal 10q monosomy and urogenital anomalies suggests the presence of a gene(s) for urogenital development on distal 10q, molecular deletion mapping has not been performed for the putative gene(s). In this study, we examined genotype-phenotype correlations in patients with distal 10q monosomy.

METHODS

This study consisted of six karyotypic males (cases 1 through 6) and four karyotypic females (cases 7 through 10) with 10q26 monosomy. Cases 3 through 5 and 7 through 10 had urinary anomalies such as vesicoureteral reflux and hypoplastic kidney, and cases 1 through 6, 8, and 9 exhibited genital anomalies such as micropenis, hypospadias, cryptorchidism, and hypoplastic labia majora. Fluorescence in situ hybridization (FISH) for 10q telomere, whole chromosome 10 painting, and microsatellite analysis for 35 loci on distal 10q were performed in cases 1 through 8.

RESULTS

FISH and whole chromosome painting confirmed distal 10q monosomy in cases 1 through 8. Microsatellite analysis revealed that hemizygosity for the region distal to D10S186 was shared by cases with urinary anomalies and that for the region distal to D10S1248 was common to cases with genital anomalies. Furthermore, it was indicated that PAX2, GFRA1, and EMX2 on distal 10q, in which the deletions could affect urinary and/or genital development, were present in two copies in cases 1 through 8.

CONCLUSIONS

The results suggest that a novel gene(s) for urinary development and that for genital development reside in the approximately 20 cM region distal to D10S186 and in the approximately 10 cM region distal to D10S1248, respectively, although it remains to be determined whether the two types of genes are identical or different.

Left atrial systolic function assessed by left atrial ejection force in patients with sick sinus syndrome and paroxysmal atrial fibrillation

We evaluated left atrial systolic function using left atrial ejection force (LAEF) in 19 patients with sick sinus syndrome (SSS) and in 20 with paroxysmal atrial fibrillation (Paf) whose ages ranged from 48 to 80 years. We also evaluated 35 normal individuals for comparison. The LAEF was calculated as 1/3 x mitral valve area x (peak velocity of A wave)2 using two-dimensional and pulsed-Doppler echocardiography according to Newton's law of motion and hydrodynamics. In normal individuals, LAEF positively correlated with age (r = 0.82, p < 0.01). Normal LAEF was calculated as 0.098 x age - 0.74 (kdynes) from the regression line. Because of this correlation, we used age-corrected LAEF (%LAEF) that was calculated as (measured LAEF / normal LAEF) x 100. The results showed that this value was 53+/-26% in patients with SSS and 54+/-26% in patients with Paf. Both were significantly lower than normal individuals (p < 0.001). Among SSS subtypes, %LAEF was lower in types II and III than in type I (51+/-14%, 37+/-19%, and 81+/-35%, respectively). In conclusion, left atrial systolic function is depressed in patients with Paf and SSS, in particular, types II and III. These results suggest that the pathological abnormalities extend not only to the sinus node but also to the left atrial muscle in patients with SSS and Paf.

Release characteristics of a short-chain fatty acid, n-butyric acid, from its beta-cyclodextrin ester conjugate in rat biological media

6(A)-O-(n-Butanoyl)-beta-cyclodextrin was prepared and its hydrolysis behavior in aqueous solutions and in rat intestinal fluids was investigated. Furthermore, the enzymatic hydrolyses of the n-butyric acid-beta-cyclodextrin conjugate using alpha-amylase and esterase were studied to gain insight into the release behavior of n-butyric acid from the conjugate. The hydrolysis of the conjugate proceeded according to a first-order kinetics in aqueous solution, and gave a V-shaped pH profile, indicating a specific acid-base-catalyzed hydrolysis at acidic and neutral-alkaline regions, respectively. The half-lives (t(1/2)) of the conjugate at pH 4.4, 6.8, and 7.4 at 37 degrees C were approximately 580, 43, and 6 days, respectively, indicating that the conjugate is stable in aqueous solution. No appreciable release of n-butyric acid from the conjugate was observed in the stomach and small intestinal contents of rats, or in the small and large intestinal homogenates of rats. On the other hand, a fast disappearance of the conjugate and an appearance of n-butyric acid were observed in the cecal and colonic contents of rats. The t(1/2) values of the disappearance were approximately 4, 1, and 6 h in 10 and 15% cecal contents and 10% colonic contents, respectively, and the appearance of n-butyric acid after 6 h was approximately 10% in the 15% cecal contents. Aspergillus oryzae alpha-amylase hydrolyzed the conjugate to small saccharide conjugates, such as the triose and maltose conjugates, but there was no appreciable release of n-butyric acid. The conjugate was less susceptible to carboxylic esterase (from porcine live), thus releasing no appreciable amounts of n-butyric acid. On the other hand, a fast release of n-butyric acid was observed when the esterase was employed after amylase hydrolysis, suggesting that two types of enzymes, sugar-degrading and ester-hydrolyzing enzymes, are necessary for the release of n-butyric acid from the conjugate in large intestinal contents.

CAG repeat length of the androgen receptor gene in Japanese males with cryptorchidism

We have analysed the CAG repeat length in exon 1 of the androgen receptor gene in 48 Japanese males with cryptorchidism and 100 fertile Japanese males. The CAG repeat length was 23.4 +/- 0.48 (mean +/- SE) (range 16-32, median 23) in cryptorchid patients and 23.5 +/- 0.29 (range 15-32, median 23) in normal males. There was no significant difference between the two groups. The expansion of the CAG repeats in exon 1 of the androgen receptor gene is unlikely to constitute a major cause of cryptorchidism.

Testicular volume in Japanese boys up to the age of 15 years

Previous studies have indicated that Japanese children grow and mature significantly faster than Caucasian children, thus calling for a separate reference standard for each skeletal and sexual maturity index. To establish normal reference values for testicular volume in Japanese boys, we studied from 1985 to 1995, 900 healthy male children of 0 to 15 years of age for medical history, physical examination, height, weight, sitting height, and head circumference measurements, Tanner sex maturity stage, and testicular size. The testicular volume was determined using a Prader orchidometer by the same observer (N.M.). Based on these data, we established the cross-sectional percentile growth curves (90th, 50th, 10th percentiles) for testicular volume of Japanese boys. The testicular volume of 3 ml was attained at 9.3 years of age (90th percentile), 11.0 years of age (50th percentile), and 12.1 years of age (10th percentile), respectively.

CONCLUSION

Swelling of the testis in Japanese children begins approximately 1 year earlier than in Swiss children in accordance with the earlier skeletal maturation in Japanese children.

Clinical and molecular studies in 15 females with ring X chromosomes: implications for r(X) formation and mental development

We report clinical and molecular findings in 15 Japanese mosaic females with r(X) chromosomes, 45,X/46,X,r(X), confirmed by fluorescence in situ hybridization (FISH) analysis for DXZ1 and whole X chromosome painting. Cases 1-3, 5-7, and 11-13 had mental retardation (MR), the remaining cases being free from MR. FISH analysis showed that XIST was absent from the r(X) chromosomes in cases 1-4 and was present on the r(X) chromosomes in cases 5-15. X-inactivation analysis for the methylation status of the AR gene indicated that, of eight cases with XIST-positive r(X) chromosomes in more than 10% (23%-62%) of lymphocytes (cases 5-12), cases 5-10 had selective X-inactivation, whereas cases 11 and 12 had active X disomy. Microsatellite analysis for multiple loci on the pericentromeric region revealed that, of 11 cases with r(X) chromosomes in more than 10% (13%-62%) of lymphocytes (cases 1, 2, and 4-12), cases 1, 2, and 5-10 had heterozygous alleles for at least one locus, whereas cases 4, 11, and 12 had single alleles for all the loci examined. The results suggest that the r(X) and normal X chromosomes could be of biparental or uniparental origin, and that mental status in females with r(X) chromosomes is determined by multiple factors, including the presence or absence of XIST on the r(X) chromosomes and the size and frequency of active r(X) chromosomes, in addition to co-incidental genetic and environmental factors.

Novel and recurrent EBP mutations in X-linked dominant chondrodysplasia punctata

Chondrodysplasia punctata (CDP) is a heterogeneous group of skeletal dysplasias characterized by stippled epiphyses. A subtype of CDP, X-linked dominant chondrodysplasia punctata (CDPX2), known also as Conradi-Hünermann-Happle syndrome, is a rare skeletal dysplasia characterized by short stature, craniofacial defects, cataracts, ichthyosis, coarse hair, and alopecia. The cause of CDPX2 was unknown until recent identification of mutations in the gene encoding Delta(8),Delta(7) sterol isomerase emopamil-binding protein (EBP). Twelve different EBP mutations have been reported in 14 patients with CDPX2 or unclassified CDP, but with no evidence of correlation between phenotype and nature of the mutation. To characterize additional mutations and investigate possible phenotype-genotype correlation, we sequenced the entire EBP gene in 8 Japanese individuals with CDP; 5 of them presented with a CDPX2 phenotypes. We found EBP mutations in all 5 CDPX2 individuals, but none in non-CDPX2 individuals. Three of these CDPX2 individuals carried novel nonsense mutations in EBPand the other two, separate missense mutations that had been reported also in different ethnic groups. Our results, combined with previous information, suggest all EBP mutations that produce truncated proteins result in typical CDPX2, whereas the phenotypes resulted from missense mutations are not always typical for CDPX2. Patients with nonsense mutations showed abnormal sterol profiles consistent with a defect in Delta(8), Delta(7) sterol isomerase. X-inactivation patterns of the patients showed no skewing, an observation that supports the assumption that inactivation of the EBP gene occurs at random in affected individuals.

Morphological changes of Babesia gibsoni grown in canine red blood cell-substituted severe combined immune deficiency mice

Canine red blood cell-substituted severe combined immune deficiency (Ca-RBC-SCID) mice were prepared for canine Babesia gibsoni infection. The Ca-RBC-SCID mice infected with B. gibsoni developed a high level of parasitemia, and showed clinical symptoms such as anemia and hemoglobinuria, which are similar to those observed in dogs infected with B. gibsoni. The B. gibsoni parasites grown in Ca-RBC-SCID mice showed marked morphological changes, including a significantly larger size of parasites than those in dogs and abundant RBCs containing 4, 8, 16, and 32 parasites. The multiple infection may have resulted from 1 parasite because the posterior end of each parasite in a multiply infected cell was connected. The parasites grown in SCID mice retained their infectivity and virulence to dogs and their morphology was dramatically restored to the original state when they were returned to dogs.