Identification of differentially expressed genes in psoriasis using expression profiling approaches.

To identify differentially expressed genes which play causal roles in pathogenesis and maintenance for psoriasis, we used BodyMapping and introduced amplified fragment length polymorphism approaches. From the BodyMap database, we selected 2007 genes which specifically expressed in epithelial tissues. Among 2007 genes, we surveyed genes which differentially expressed in involved or uninvolved psoriatic lesional skin samples compared with atopic dermatitis, mycosis fungoides, and normal skin samples. As a result of surveying 2007 genes, 241 genes were differentially expressed only in involved psoriatic skin but not in the other samples. Hierarchical cluster analysis of gene expression profiles showed that 13 independent psoriatic-involved skin samples clustered tightly together, reflecting highly similar expression profiles. Using the same 2007 gene set, we examined gene expression levels in five serial lesions from distal uninvolved psoriatic skin to involved psoriatic plaque. We identified seven genes such as alpha-1-microglobulin/bikunin precursor, calnexin, claudin 1, leucine zipper down-regulated in cancer 1, tyrosinase-related protein 1, Yes-associated protein 1, and unc-13-like protein (Coleonyx elegans) which show high-expression levels only in uninvolved psoriatic lesions. These seven genes, which were reported to be related to apoptosis or antiproliferation, might have causal roles in pathophysiology in psoriasis.

Unconstrained and non-invasive measurement of heart-beat and respiration periods using a phonocardiographic sensor.

With the rapid growth in the number of elderly people in the population, interest in health monitoring is increasing. Therefore the development of an unconstrained and non-invasive vital signs measurement system could be important for monitoring health status at home or in hospitals or nursing facilities. A simple system is proposed for measuring heart-beat and respiration periods for home healthcare. This was achieved with a phonocardiographic (PCG) sensor set on a water-mat or air-mat. The PCG sensor was an acceleration sensor that extracted the vibration of the mat caused by heart-beat and respiration. By calculating an autocorrelation function of the fully rectified sensor output or by local pattern matching between the rectified output and a reference signal (pre-memorised for each subject), the system measured the average and instantaneous periods of both heart-beat and respiration. Results showed that these periods were measured to a similar level of accuracy as for the electrocardiogram and thermistor respiration pickup. The comparative accuracies were within the following ranges: average heartbeat 0.19% to 0.67%, instantaneous heartbeat 0.53% to 1.15%, average respiration 0.51% to 2.17%, and instantaneous respiration 2.51% to 5.20%.

Expression of Na+/Ca(2+) exchanger (NCX1) gene in the developmental mouse embryo and adult mouse brain.

The Na(+)/Ca(2+) exchanger gene, NCX1, is widely expressed in many tissues, encoding several isoforms through alternative RNA splicing. NCX1 deficient mice are known to be lethal at embryonic day 9-10 (E9-10). However, its expression pattern during embryogenesis is largely unknown. Therefore, to identify and compare the localization and alternatively spliced isoforms of NCX1 mRNA expressed in the developmental stages, we analyzed the mouse embryo. Northern blot analysis demonstrated that NCX1 mRNA was expressed from the earliest stage examined, E7. In situ hybridization analysis revealed that NCX1 mRNA was expressed in the heart alone until E10.5. However, at E14.5 and 16.5, NCX1 mRNA was expressed not only in the heart, but also in neuronal cells. In addition, the expression of NCX1 mRNA in the adult brain was most abundant in the hippocampus. Using reverse transcription-polymerase chain reaction (RT-PCR), we also identified the alternatively spliced isoforms expressed during each developmental stage. The restricted expression of the NCX1 gene suggested that NCX1 may play an important role in the developing mouse embryo.

Targeted disruption of Na+/Ca2+ exchanger gene leads to cardiomyocyte apoptosis and defects in heartbeat.

Ca(2+), which enters cardiac myocytes through voltage-dependent Ca(2+) channels during excitation, is extruded from myocytes primarily by the Na(+)/Ca(2+) exchanger (NCX1) during relaxation. The increase in intracellular Ca(2+) concentration in myocytes by digitalis treatment and after ischemia/reperfusion is also thought to result from the reverse mode of the Na(+)/Ca(2+) exchange mechanism. However, the precise roles of the NCX1 are still unclear because of the lack of its specific inhibitors. We generated Ncx1-deficient mice by gene targeting to determine the in vivo function of the exchanger. Homozygous Ncx1-deficient mice died between embryonic days 9 and 10. Their hearts did not beat, and cardiac myocytes showed apoptosis. No forward mode or reverse mode of the Na(+)/Ca(2+) exchange activity was detected in null mutant hearts. The Na(+)-dependent Ca(2+) exchange activity as well as protein content of NCX1 were decreased by approximately 50% in the heart, kidney, aorta, and smooth muscle cells of the heterozygous mice, and tension development of the aortic ring in Na(+)-free solution was markedly impaired in heterozygous mice. These findings suggest that NCX1 is required for heartbeats and survival of cardiac myocytes in embryos and plays critical roles in Na(+)-dependent Ca(2+) handling in the heart and aorta.

Isolation and characterization of Na+/Ca2+ exchanger gene and splicing isoforms in mice.

The Na+/Ca2+ exchanger gene NCX1 is ubiquitously expressed in mammalian tissues, and encodes several isoforms through alternative RNA splicing. In this report, we describe the gene structure that gives rise to the multiple isoforms, and the tissue-specific expression of these isoforms in mice. The mouse NCX1 gene contains a cluster of six exons (A, B, C, D, E, and F) which encode a variable region in the large intracellular loop of the protein, as previously reported in rabbits and humans. Using reverse transcription-polymerase chain reaction (RT-PCR), expression of the isoforms was examined in several tissues. We also identified a novel splice variant, which originate from exons A, C, D, and F. These findings provide new insights into the significance of the large repertoire of NCX1 isoforms.

Insertional mutation of the murine kisimo locus caused a defect in spermatogenesis.

Spermatogenesis is a developmental process that occurs in several phases and is regulated by a large number of gene products. An insertional transgenic mouse mutant (termed kisimo mouse) has been isolated that results in abnormal germ-cell development, showing abnormal elongated spermatids in the lumina of seminiferous tubules. We cloned the disrupted locus of kisimo and identified a novel testis-specific gene, THEG, which is specifically expressed in spermatids and was disrupted in the transgenic mouse. The yeast two-hybrid screening method revealed that THEG protein strongly interacts with chaperonin containing t-complex polypeptide-1epsilon, suggesting that THEG protein functions as a regulatory factor in protein assembly. Our findings indicate that the kisimo locus is essential for the maintenance of spermiogenesis and that a gene expression disorder may be involved in male infertility.

Serial water changes in human skeletal muscles on exercise studied with proton magnetic resonance spectroscopy and imaging.

In vivo 1H-magnetic resonance imaging (MRI) enabled us to study the distribution of water in living tissues and to document changes in human skeletal muscles during physical exercise. The purpose of the present study was to determine the total muscle water changes after exercise using water in 1H-MR spectroscopy and to compare these changes to the signal intensity change on T2*-weighted images and/or to the T2 value change. Seven young male volunteers were positioned in a 1.5 T Philips MR imaging system. They were then asked to dorsiflex their ankle joint against a 2 kg weight once every 2 seconds for 2 minutes. The peak height of water declined according to the clearance curve after exercise in all seven cases with the 1H-MRS similar to the signal intensity. The increasing rate at peak height of total muscle water exceeded both the signal intensity and the T2 value because the water peak height on the 1H-MRS included the extracellular water. In addition, we measured the changes in signal intensity in both calf muscles after walking race exercise. The time intensity curves were used to draw a clearance curve for each muscle group after exercise. It was possible to discern which muscle was used most from the T2*-weighted image that was obtained once after exercise.

Psychiatric disorders of pre-adolescence in Japan.

We have classified 200 pre-adolescent patients, with whom we have met during the last three years, into the following four types: school refusal and obsessive behavior, psychosomatic disorders, depressive reactions, and schizophrenic disorders. During our therapeutic process, we realized that even though their symptoms seemed varied and severe, they disappeared after comparatively short periods. The pre-adolescent period is a turning point at which the children depart from their earlier relationships with parents and start to form new ones with friends. We facilitated the patients' developmental process in this period so that they would recover naturally by themselves. However, when we looked at the social phenomena which influence the family and children, we noticed that some factors interfered with the pre-adolescents trying to get over the above-mentioned turning point.