Measurement of urinary 8-oxo-7,8-dihydro-2-deoxyguanosine in a novel point-of-care testing device to assess oxidative stress in children.

BACKGROUND: 8-oxo-7,8-dihydro-2-deoxyguanosine (8-oxodG), also known as 8-hydroxy-2'-deoxyguanosine (8-OHdG), is an oxidatively damaged nucleobases of DNA and is excreted into urine. Therefore, its urinary level is used as a sensitive marker for oxidative stress (OS). Although it can be measured by enzyme-linked immunosorbent assay (ELISA), its application to clinical pediatrics remains limited. Recently, a novel automatic analyzer (model no. ICR-001: Techno Medica Co., Ltd., Japan) has been developed for point-of-care testing (POCT) to measure urinary 8-oxodG. We verified the reliability of the value of urinary 8-oxodG measured by this novel analyzer and to set the age-related reference intervals. METHOD: We obtained random urine samples from 100 healthy Japanese adults and 157 healthy Japanese children aged 0-15years. Urinary 8-oxodG was determined using two methods: competitive immunochromatography using a novel automatic analyzer (ICR-001) and another was ELISA. RESULTS: Both urinary 8-oxodG and urinary creatinine measured by ICR-001 correlated well with those measured by ELISA (r(s)=0.945, p<0.0001) and an enzymatic method (r(s)=0.988, p<0.0001). Age-related reference for 8-oxodG corrected by creatinine were highest in the youngest subjects and decreased until adolescence, consistent with published data by ELISA. CONCLUSION: A new automatic analyzer that measures urinary 8-oxodG can be used as a POCT for the assessment of OS levels in children.

Molecular characterization of structure and tissue distribution of chicken neurotensin receptor.

Neurotensin, a tridecapeptide, is distributed in a wide range of tissues and exhibits multiple functions through its receptors. Hitherto molecular characterization of the neurotensin receptor has been reported in mammalian, amphibian, and fish species but not in avian species. In this study, we cloned the cDNA encoding chicken neurotensin receptor from the duodenum and characterized its primary structure, biological activity and distribution in the gastrointestinal tract. The cDNA encoded a protein consisting of 399 amino acids that had significant overall sequence homology to other vertebrate neurotensin receptor 1 with higher extent in the seven transmembrane domains. Chicken neurotensin increased intracellular Ca(2+) concentrations in human embryonic kidney 293 cells transiently expressing the chicken neurotensin receptor 1. Real-time PCR analysis showed that chicken neurotensin receptor 1 mRNA is expressed throughout the gastrointestinal tract with markedly higher level in the colon/rectum. These results indicate that the chicken neurotensin receptor 1 is involved in gastrointestinal functions through an intracellular signaling pathway accompanied by an increase in Ca(2+) levels.

Opening of holes in liposomal membranes is induced by proteins possessing the FERM domain.

The destabilization of vesicles caused by interactions between lipid bilayers and proteins was studied by direct, real-time observation using high-intensity dark-field microscopy. We previously reported that talin, a cytoskeletal submembranous protein, can reversibly open stable large holes in giant liposomes made of neutral and acidic phospholipids. Talin and other proteins belonging to the band 4.1 superfamily have the FERM domain at their N-terminal and interact with lipid membranes via that domain. Here, we observed that band 4.1, ezrin and moesin, members of the band 4.1 superfamily, are also able to open stable holes in liposomes. However, truncation of their C-terminal domains, which can interact with the N-terminal FERM domain, impaired their hole opening activities. Oligomeric states of ezrin affected the capability of the membrane hole formation. Phosphatidylinositol bisphosphate (PIP2), which binds to the FERM domain and disrupts the interaction between the N and C termini of the band 4.1 superfamily, down-regulates their membrane opening activity. These results suggest that the intermolecular interaction plays a key role in the observed membrane hole formation.

Complete sequencing and characterization of 21,243 full-length human cDNAs.

As a base for human transcriptome and functional genomics, we created the "full-length long Japan" (FLJ) collection of sequenced human cDNAs. We determined the entire sequence of 21,243 selected clones and found that 14,490 cDNAs (10,897 clusters) were unique to the FLJ collection. About half of them (5,416) seemed to be protein-coding. Of those, 1,999 clusters had not been predicted by computational methods. The distribution of GC content of nonpredicted cDNAs had a peak at approximately 58% compared with a peak at approximately 42%for predicted cDNAs. Thus, there seems to be a slight bias against GC-rich transcripts in current gene prediction procedures. The rest of the cDNAs unique to the FLJ collection (5,481) contained no obvious open reading frames (ORFs) and thus are candidate noncoding RNAs. About one-fourth of them (1,378) showed a clear pattern of splicing. The distribution of GC content of noncoding cDNAs was narrow and had a peak at approximately 42%, relatively low compared with that of protein-coding cDNAs.

Does fear of falling relate to low physical function in frail elderly persons?: associations of fear of falling, balance, and gait.

Falls are a major public health problem for older people. Recent research suggests that fear of falling may be a more pervasive and serious problem than falls among the elderly. The present study was conducted to determine whether frail elderly persons with fear of falling have lower physical function. A total of 47 subjects (aged 73 to 95) were recruited from a geriatric health services facility in Osaka. Physical function including balance, mobility, and muscular strength were measured using the following tests: Timed up & go test (TUG), functional reach test, single limb stance with eyes open, ten-meter walk, and knee extensor strength. Twenty-nine subjects (62%) had fear of falling and 18 (38%) had no fear of falling. There was no significant difference in age, sex, or the proportion using assistive devices. Results from the statistical tests showed that there were no differences in physical function, except in the functional reach test. The ratio of TUG to 10 m walk was used to determine the association between balance and mobility. In frail elderly persons with fear of falling and in those without fear of falling, the means of the ratios were 1.20 (SD=0.27) and 1.03 (SD=0.16), respectively. The ratios for frail elderly persons with fear of falling were higher (p=0.024) than the frail elderly without fear of falling. Our study suggests that even if frail elderly individuals walk slowly, they are not afraid of falling if there is a feasible balance function. We conclude that, in low-functioning frail elderly, fear of falling is associated with a combination of balance function and gait speed.