L-DOPA produced nitric oxide in the vitreous and caused greater vasodilation in the choroid and the ciliary body of melanotic rats than in those of amelanotic rats

The nitrogen cycle initiates direct reduction of N2 to NH3 by enzymatic reactions. We hypothesize that L-dihydroxyphenylalanine (L-DOPA), a catecholamine, could be a source of nitric oxide (NO). In order to determine whether L-DOPA generates NO and induces any biological change in the eye, we measured the generation of NO in vitro and in vivo, and investigated the histopathological changes caused by injection of L-DOPA into the vitreous of rats. We also hypothesized that melanin granules may affect the generation of NO during the metabolism of L-DOPA, since L-DOPA is a precursor of melanin in the brain and the eye. Therefore, we compared the effects of L-DOPA on the generation of NO between amelanotic and melanotic rats. NO was measured as diffusion currents by NO electrodes. In vitro, various concentrations of L-DOPA (5, 29.9, 79.4, 152.7, and 249 microM) were added to the medium. The inhibition of NO generation by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazole-1-oxyl 3-oxide (carboxy-PTIO) was tested. In vivo, NO generation in the vitreous of rats was measured and the eyes were enucleated under anesthesia after L-DOPA injection. The ocular tissues were subjected to histological examination. NO was produced from L-DOPA in a dose-dependent manner and was scavenged by carboxy-PTIO in vitro. NO in the vitreous of melanotic rats was generated from L-DOPA. Histological examination with hematoxylin-eosin staining revealed vasodilation in the ciliary vessels and the choroid after L-DOPA injection. Both effects were greater in melanotic rats than in amelanotic rats. The vasodilation may be attributable to NO as well as to superoxides, which can be regulated by the existence of melanin.

Mutation screening and CAG repeat length analysis of the androgen receptor gene in Klinefelter's syndrome patients with and without spermatogenesis

BACKGROUND

Mutations of the androgen receptor (AR) gene give rise to a wide array of phenotypic abnormalities. A systematic analysis of the AR gene in patients with 47,XXY has not previously been performed.

METHODS

Mutations of the AR gene and expansion of the CAG repeats in exon 1 of the AR gene were studied in 13 patients with Klinefelter's syndrome either with (n = 1) or without (n = 12) spermatogenesis.

RESULTS

No abnormalities in the AR gene were detected by single strand conformational polymorphism analysis. The CAG lengths ranged from 17 to 27 (mean +/- SD 22.8 +/- 3.3, median 23) for Klinefelter patients or from 17 to 28 (mean +/- SD 23.2 +/- 2.6, median 23) for control subjects. X-inactivation analysis for the methylation status of the AR gene was performed in seven patients who were heterozygous for CAG repeats of different length, showing that the longer CAG repeat alleles underwent random but more frequent inactivation in five patients and skewed inactivation in two.

CONCLUSIONS

An AR gene abnormality does not constitute an important factor for impaired spermatogenesis in patients with Klinefelter's syndrome.

Compound effects of point mutations causing campomelic dysplasia/autosomal sex reversal upon SOX9 structure, nuclear transport, DNA binding, and transcriptional activation

Human mutations in the transcription factor SOX9 cause campomelic dysplasia/autosomal sex reversal. Here we identify and characterize two novel heterozygous mutations, F154L and A158T, that substitute conserved "hydrophobic core" amino acids of the high mobility group domain at positions thought to stabilize SOX9 conformation. Circular dichroism studies indicated that both mutations disrupt alpha-helicity within their high mobility group domain, whereas tertiary structure is essentially maintained as judged by fluorescence spectroscopy. In cultured cells, strictly nuclear localization was observed for wild type SOX9 and the F154L mutant; however, the A158T mutant showed a 2-fold reduction in nuclear import efficiency. Importin-beta was demonstrated to be the nuclear transport receptor recognized by SOX9, with both mutant proteins binding importin-beta with wild type affinity. Whereas DNA bending was unaffected, DNA binding was drastically reduced in both mutants (to 5% of wild type activity in F154L, 17% in A158T). Despite this large effect, transcriptional activation in cultured cells was only reduced to 26% in F154L and 62% in A158T of wild type activity, suggesting that a small loss of SOX9 transactivation activity could be sufficient to disrupt proper regulation of target genes during bone and testis formation. Thus, clinically relevant mutations of SOX9 affect protein structure leading to compound effects of reduced nuclear import and reduced DNA binding, the net effect being loss of transcriptional activation.

Characteristics of wine produced by mushroom fermentation

Saccharomyces cerevisiae is the main microorganism used in wine brewing, because this microbe has potent ability to produce alcohol dehydrogenase. We have recently discovered that some genera of mushroom produced alcohol dehydrogenase, and made wine by using a mushroom in place of S. cerevisiae. The highest alcohol concentration in this wine was achieved with Pleurotus ostreatus (2.6 M, 12.2%). In the case of Agaricus blazei, the same alcohol concentration (1.7 M, 8%) was produced under both aerobic and anaerobic conditions. This wine produced by A. blazei contained about 0.68% beta-D-glucan, which is known to have a preventive effects against cancer. The wine made by using Flammulina velutipes showed thrombosis-preventing activity, giving a prolonged thrombin clotting time 2.2-fold that of the control. Thus, the wine made by using mushroom seems to be a functional food which can be expected to have preventive effects against cancer and thrombosis.

Ultra-high-resolution scanning electron microscopic studies on the membrane system of the rat parietal cells after tetragastrin stimulation

The membrane system of the rat parietal cells in the resting state and after stimulation with tetragastrin (gastrin) was examined by ultra-high-resolution scanning electron microscopy after removal of the cytoplasmic matrix by the aldehyde-osmium-DMSO-osmium procedure. The intracellular canaliculus was lined with numerous microvilli. Viewed from the cytoplasmic side, the intracellular canaliculi appeared as an arborized system of cactus-like structures with numerous holes about 100 nm in diameter corresponding to the basal openings of the microvilli. The intracellular canaliculi were more developed after gastrin stimulation than in the resting state. In resting cells, most of the tubulovesicles were isolated, 100-200 nm in diameter, spherical or tubular in shape. After gastrin stimulation, these structures were interconnected by slender tubules of about 30 nm in diameter forming together tubulovesicular network. Stereo SEM views clearly demonstrated that the tubulovesicular network was connected with the intracellular canaliculus by the slender connecting tubulus. The increase in the canalicular membrane area and the depletion of tubulovesicles is explained by the transfer of the tubulovesicular membrane to the intracellular canaliculus. In the resting parietal cell, the microvilli are slender and their interior is packed with microfilaments. After gastrin stimulation, the microvilli are swollen and their interior is edematous. These morphological changes seem to indicate the accumulation of fluid in the microvilli after gastrin stimulation.

Undermasculinized genitalia in a boy with an abnormally expanded CAG repeat length in the androgen receptor gene

We report an 11-year-old boy with undermasculinized genitalia and an abnormally expanded CAG repeat length at exon 1 of the androgen receptor (AR) gene. He had microphallus and scrotal hypospadias with chordee, and underwent urethroplasty at 4 years of age. At 11 years of age, a gonadotropin releasing hormone (GnRH) test yielded a relatively high leutinizing hormone (LH) response (0.7-->20.4 IU/l) and a relatively low follicle-stimulating hormone (FSH) response (1.7-->4.8 IU/l), and an human chorionic gonadotropin (hCG) test showed sufficient responses of testosterone (0.7-->23.0 nmol/l) and dihydrotestosterone (0.38-->2.95 nmol/l). The CAG repeat length was 44 for the boy and ranged from 12 to 32 for 100 control males. The DNA sequences of the AR gene were normal for the exons 1-8 and for the splice donor, splice acceptor and branch sites. The markedly expanded CAG repeat length appears to be relevant to the undermasculinized genitalia of this boy, because such an expandsion, which has previously been reported only in spinal and bulbar muscular atrophy, is known to reduce AR function.

[A surgical treatment for ischemic heart disease associated with systemic lupus erythematodes: report of a case]

We reported a case of coronary artery bypass grafting (CABG) associated with systemic lupus erythematodes (SLE). A 45-year-old male who had been treated for SLE with prednisolone for 9 years was transferred to our department for a surgical treatment due to ischemic heart disease (IHD). We successfully performed CABG resolving various perioperative complications. The intensive care is indispensable in the case of IHD with SLE.

Growth hormone and gonadotropin-releasing hormone analog therapy in haploinsufficiency of SHOX

We report on GH (0.5 IU or 0.17 mg/kg/week) and GnRH analog (GnRHa, 60 microg/kg, every 4 weeks) therapy in SHOX haploinsufficiency. Case 1 was a 46,XY boy with microdeletion of the Y chromosomal pseudoautosomal region. At 7 years of age, he exhibited short stature (-3.9 SD) with a reduced growth rate (3.8 cm/year), short 4th metacarpals, and mild Madelung deformity. GH therapy resulted in a marked increase in height velocity (10.7 cm/year in the first year). Case 2 was a 46,XX girl with a heterozygous nonsense mutation of SHOX (C674T). At 6 years of age, she presented with short stature (-3.3 SD) with a low height velocity (4.0 cm/year). GH therapy caused a moderate increase in height velocity (6.6 cm/year in the first year and 6.0 cm/year in the second year) before puberty. Because of breast development, she received GnRHa from 9 8/12 years of age. At 10 10/12 years of age, she had mild shortening and borderline curvature of radius. Case 3 was a girl with a 46,X,der(X)t(X;2)(p22.3;p21) karyotype. She was treated with GH from 6 to 14 years of age, and also with GnRHa from 12 to 15 years of age. Her height remained around mean -4 SD, with no discernible alteration of height velocity. At 17 years of age, she had short stature (-4.1 SD), bilateral cubitus valgus, Madelung deformity, and full breast development. The results suggest that GH therapy may have variable statural effects in SHOX haploinsufficiency as in most disorders including Turner syndrome, and that GnRHa therapy after pubertal entry may be insufficient to prevent the development of skeletal lesions such as Madelung deformity.

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.