Enolase-1 expression in the stratum corneum is elevated with parakeratosis of atopic dermatitis and disrupts the cellular tight junction barrier in keratinocytes.

OBJECTIVE: Previous studies have shown that enolase-1 (ENO1) in the stratum corneum (SC) is more highly expressed in patients with atopic dermatitis (AD) than in healthy individuals, suggesting that it is a novel biomarker for evaluating skin condition in patients with AD. However, the mechanism underlying high ENO1 expression in the SC and its pathological relevance in AD are unclear. In this study, the relationship between ENO1 expression and keratinization of epidermis was investigated, and the role of high ENO1 expression in keratinocytes was characterized. METHODS: ENO1 expression and morphological characteristics were examined in SC from the cheeks of 24 patients with AD. Additionally, the localization of ENO1 in the excised human epidermis was observed. Moreover, to analyse the role of ENO1 in cellular barrier function, tight junction proteins (TJs) and transepithelial electrical resistance (TEER) in keratinocytes with ENO1 overexpression were evaluated. Furthermore, the localization of ENO1 and plasminogen in keratinocytes was evaluated by immunostaining, and the cellular barrier function in keratinocytes was examined after treatment with tranexamic acid (TXA). RESULTS: ENO1 expression was substantially correlated with the rate of nucleated corneocytes in AD. In addition, ENO1 localized in the basal to spinous layers, but was its expression dramatically decreased in healthy human SC. ENO1 overexpression in human epidermal keratinocytes reduced the expression of TJs (claudin-4, E-cadherin, tricellulin, and occludin) and TEER, and treatment with anti-ENO1 IgG reversed these effects. ENO1 colocalized with plasminogen in keratinocytes. Treatment with TXA rescued the ENO1-induced reductions in TJ and TEER expression. CONCLUSION: We found a substantial correlation between ENO1 expression and the rate of nucleated corneocytes in AD and decreased ENO1 expression with nuclear disappearance. These results suggest that high ENO1 expression in the SC of AD is caused by deficient keratinization, which is an AD characteristic. Moreover, ENO1 overexpression in keratinocytes promoted dysfunction of TJ dynamics, leading to reduced integrity of the cellular barrier, and these effects might be mediated by plasmin activity. We propose that ENO1 is a useful indicator of parakeratosis and might have a potential role in cellular TJ barrier function in the epidermis.

Does surgery improve live birth rates in patients with recurrent miscarriage caused by uterine anomalies?

We found that congenital uterine anomalies have a negative impact on reproductive outcome in recurrent-miscarriage couples, being associated with further miscarriage with a normal embryonic karyotype. There has been no study comparing live birth rates between patients with and without surgery. We conducted a prospective study to prove that surgery for a bicornuate or septate uterus might improve the live birth rate. A total of 170 patients with congenital uterine anomalies suffering two or more miscarriages were examined. The live birth rate after ascertainment of anomalies, cumulative live birth rate and infertility rate, were compared between patients with and without surgery. In patients with a septate uterus, the live birth rate (81.3%) at the first pregnancy after ascertainment of anomalies with surgery tended to be higher than that (61.5%) in those without surgery. The infertility rates were similar in both groups, while the cumulative live birth rate (76.1%) tended to be higher than without surgery (60.0%). Surgery showed no benefit in patients with a bicornuate uterus for having a baby, but tended to decrease the preterm birth rate and the low birth weight. The possibility that surgery has benefits for having a baby in patients with a septate uterus suffering recurrent miscarriage could not be excluded.

Francium ion source with novel methods of target heating and beam characterization.

We have developed a novel ion source and beam diagnostic system for the production and detection of radioactive francium (Fr) isotopes. The Fr ions are produced using a fusion-evaporation reaction at the RIKEN Nishina Center, Japan. The installation of an infrared heater has enabled a precise and rapid control of the target temperature, and the newly developed diagnostic system allows for a quantitative characterization of the extracted ion beam. With the new system, an analysis of the Fr208-211 isotopes has been performed. Additionally, the flux of Fr210 ions has been estimated as 6.7 × 106 s-1 corresponding to an extraction efficiency of 24.5% and a beam purity of 1.6 × 10-5.

Psychological adjustment and psychosocial stress among Japanese couples with a history of recurrent pregnancy loss.

BACKGROUND: Little is known about the effects of recurrent pregnancy loss (RPL) on the psychological adjustment of couples. The aim of this study was to elucidate psychological adjustment and RPL-associated psychosocial stress affecting Japanese couples with a history of RPL, focusing on gender differences and quality of the marital relationship. METHODS: The study included 76 RPL couples who visited the outpatient clinic of a tertiary hospital. They completed self-administered questionnaires that assessed RPL-associated stress, quality of their marital relationship (Quality Marriage Index, QMI), depression (Beck Depression Index) and anxiety (State-Trait Anxiety Inventory). RESULTS: Women showed significantly higher levels of depression, anxiety and RPL-associated personal and social stress compared with men. Although there were no differences in QMI scores and RPL-associated marital stress between men and women, women with a low perception of marital relationship quality (low QMI) had significantly higher levels of depression and anxiety compared with women with a moderate or high QMI. In contrast, depression and anxiety scores did not differ according to the quality of the marital relationship among men. Of 76 couples, 26 men (34%) and 45 women (59%) who had considered professional mental health consultations regarding their RPL status but had not yet initiated the process were more depressed and anxious than 48 men and 24 women, respectively, who had never considered such consultation. CONCLUSIONS: Women were significantly more distressed than men. Poor quality of the marital relationship was significantly associated with impaired psychological adjustment among women, but not among men. These gender discrepancies may foster a mutual worsening of psychological adjustment and marital relationships in RPL couples. The need to seek help not only in women but also in a substantial portion of men suggests the importance of couple-based psychological care in the management of RPL.

A 7-hydroxymethyl sulfate ester as an active metabolite of 7,12-dimethylbenz[alpha]anthracene.

7-Hydroxymethyl-12-methylbenz[alpha]anthracene (7-HMBA), a carcinogenic major metabolite of 7,12-dimethylbenz[alpha]anthracene (DMBA) in liver, was transformed by liver cytosolic sulfotransferase to reactive 7-HMBA sulfate, which is mutagenic toward Salmonella typhimurium strain TA98. The mutagenicity of 7-HMBA in the presence of hepatic sulfotransferase was much higher than that of DMBA or 7-HMBA in the presence of hepatic monooxygenase.

Identification of the pyramidal tract by neuronavigation based on intraoperative diffusion-weighted imaging combined with subcortical stimulation.

BACKGROUND/AIMS: To identify the pyramidal tract by neuronavigation based on intraoperative diffusion-weighted imaging (iDWI) combined with subcortical stimulation. METHODS: Seven patients with brain tumors near the deep white matter underwent resection surgery using neuronavigation based on iDWI to visualize white matter bundles. Subcortical electrical stimulation was performed and electromyography was measured at the extremities when surgical manipulation came near the position corresponding to the depicted bundle. We validated the bundle depicted on iDWI by considering the responses to subcortical stimulation and the distance between the stimulation site and the depicted bundle. RESULTS: Positive motor-evoked potentials were detected in 5 of 7 patients (8 stimulations) and the distance from the stimulation site to the depicted bundle was 0-4.7 mm (mean +/- SD, 1.4 +/- 2.1 mm). Negative (no) responses were obtained in all patients when the distance was more than 5 mm. The neuronavigation system had an average error of 0.79 +/- 0.25 mm and a maximum error of 2.0 mm (n = 16). CONCLUSION: Neuronavigation based on iDWI combined with subcortical stimulation allowed surgeons to identify the pyramidal tract and avoid inadvertent injury. Our findings demonstrate that the white matter bundles depicted by iDWI can contain the pyramidal tract.

[Minimally invasive cardiac surgery for transposition of the great arteries in neonates].

We evaluated our results of arterial switch operation (Jatene) for complete transposition of the great arteries between May 2003 and October 2005 particularly concerning various operation-related durations. Twenty neonates were studied. The mean age and body weight were 11.6 +/- 2.7 (range 5 to approximately 15) days and 3.0 +/- 0.4 kg, respectively. Duration of anesthesia, operation, extracorporeal circulation (ECC), and aortic cross-clamp were 199.4 +/- 30.1, 162.7 +/- 29.9, 91.6 +/- 8.8 and 59.8 +/- 8.1 minutes, respectively. Time differences between anesthesia and operation, operation and ECC, ECC and aortic cross-clamp were calculated, and their correlations with the duration of anesthesia were investigated. The items, whose coefficient of correlation with anesthetic time was greater than 0.6 were operation time, ECC time, aortic cross-clamp time, operation time minus ECC time, and operation time after ECC come-off. Furthermore, the operation time after ECC come-off was strongly correlated with plasma lactate concentrations and intraoperative bleeding. In conclusion, the time required for hemostasis and closure of the chest should be as short as possible. Therefore secure anastomoses with least hemorrhage possible is important.

Comparison of DNA methylation patterns among mouse cell lines by restriction landmark genomic scanning.

Restriction landmark genomic scanning (RLGS) is a novel method which enables us to simultaneously visualize a large number of loci as two-dimensional gel spots. By this method, the status of DNA methylation can efficiently be determined by monitoring the appearance or disappearance of spots by using a methylation-sensitive restriction enzyme. In the present study, using RLGS with NotI, we examined, in comparison with a brain RLGS profile, the status of DNA methylation of more than 900 loci among three types of mouse cell lines: the embryonal carcinoma cell line P19, the stable mesenchymal cell line 10T1/2, and our established neuroepithelial (EM) cell lines. We found that the relative numbers of RLGS spots which appeared were less than 3.3% of those surveyed in all cell lines examined. However, 5 to 14% of spots disappeared, the numbers increasing with an increase in the length of the culture period, and many spots were commonly lost in 10T1/2 and in three EM cell lines. Thus, for these cell lines, many more spots disappeared than appeared. However, the numbers of spots disappearing and appearing were well balanced, and the ratio in P19 cells was almost equal to that in liver cells in vivo. These RLGS experimental observations suggested that permanent cell lines such as 10T1/2 are hypermethylated and that our newly established EM cell lines are also becoming heavily methylated at common loci. On the other hand, methylation and demethylation seem to be balanced in P19 cells in a manner similar to that in in vivo liver tissue.

Role of chromosome loss in ras/myc-induced Syrian hamster tumors.

It has been shown previously that normal Syrian hamster embryo cells are neoplastically transformed by transfection with two cooperating oncogenes, v-myc plus v-Ha-ras. Karyotypic analyses of the cells from the tumors revealed a nonrandom chromosome change, monosomy of chromosome 15. In order to clarify the role of chromosome loss in these tumor cells with defined oncogene alterations, molecular and cytogenetic studies were performed on hybrids between normal Syrian hamster embryo cells and ras/myc tumor cells. Following fusion of the tumor cells with the normal cells which are not immortal, the majority of the cell hybrids senesced after less than or equal to 20 population doublings indicating that immortality was recessive. Some of the hybrids escaped senescence and grew indefinitely. These immortal hybrid cells retained the expected numbers of chromosome 15 indicating that escape from senescence did not involve loss of this chromosome. The tumorigenicity and anchorage-independent growth of the nonsenescent hybrids were still suppressed significantly. In these suppressed hybrid cells, RNAs complementary to the v-Ha-ras and v-myc oncogenes were expressed. Furthermore, radioimmune precipitation with a monoclonal antibody to p21ras of [35S]methionine-labeled cell extracts followed by polyacrylamide gel electrophoresis/sodium dodecyl sulfate electrophoresis showed that the suppressed hybrid cells contained high levels of the mutated ras protein. These results indicate that tumorigenicity is suppressed in the hybrids even though the oncogenes are expressed. When the hybrid cells were passaged, anchorage-independent variants appeared in the cultures. At this time, morphological changes occurred in the cultures and the cells were tumorigenic. Karyotypic analyses of the transformed segregants versus the parental hybrid cells revealed a nonrandom loss of one copy of chromosome 15 in the transformed segregants. No other nonrandom chromosome change was observed. These results suggest that the loss of chromosome 15 results in the loss of a cellular tumor suppressor gene which effects a phenotypic change necessary for expression of neoplastic transformation. In addition, the cellular factors responsible for the senescence of the hybrids may provide another mechanism involved in suppressing tumorigenicity.

Cholesterol alpha- and beta-epoxides as obligatory intermediates in the hepatic microsomal metabolism of cholesterol to cholestanetriol.

A high performance liquid chromatographic method for the good separation and direct determination of cholesterol alpha-epoxide (5,6 alpha-epoxy-5 alpha-cholestan-3 beta-ol) and beta-epoxide (5,6 beta-epoxy-5 beta-cholestan-3 beta-ol) was introduced to the study of microsomal lipid peroxidation-mediated oxygenation of the cholesterol double bond. In the presence of NADPH, FeSO4, and ADP, bovine liver microsomes converted [4-14C] cholesterol to the alpha-epoxide, beta-epoxide, and cholestanetriol (5 alpha-cholestane-3 beta,5,6 beta-triol) in the ratio 1.0:4.3:0.7. Obligatory intermidiacy of both cholesterol alpha- and beta-epoxides and essential role of microsomal cholesterol epoxide hydratease in the conversion of cholesterol to cholestanetriol were established by using the isotope trapping method as well as the cholesterol epoxide hydratase inhibitor, 5,6 alpha-imino-5 alpha-cholestan-3 beta-ol. Hepatic microsomal P-450 played no appreciable role in the epoxidation of cholesterol. Microsomal cholesterol epoxide hydratase was with no doubt found to differ in nature from microsomal xenobiotic epoxide hydratase. Microsomal hydrolysis of styrene oxide and safrole oxide (0.1 mM each) was almost completely inhibited by 3,3,3-trichloro-1-propene oxide (1 mM) but not by 5,6 alpha-imino-5 alpha-cholestan-3 beta-ol (1 mM). However, microsomal hydrolysis of both cholesterol alpha- and beta-epoxides was remarkably accelerated by 3,3,3-trichloro-1-propene oxide and inhibited by 5,6 alpha-imino-5 alpha-cholestan-3 beta-ol.

A mechanism for epoxidation of cholesterol by hepatic microsomal lipid hydroperoxides.

Evidence was obtained, using cis-stilbene as a model substrate, for the participation of peroxy and/or oxy radicals in epoxidation of cholesterol by rat liver microsomal phospholipid hydroperoxides and a ferrous ion-ADP complex. Under the conditions used, cholesterol was epoxidised to the alpha- and beta-epoxides in the ratio 1:2-4, and cis-stilbene to trans-stilbene oxide without concomitant formation of the cis-oxide. Microsomal phospholipid hydroperoxides could be replaced with methyllinoleate monohydroperoxide for the epoxidation of both substrates. The hydroperoxide-mediated epoxidations were completely inhibited by alpha-tocopherol and t-butylhydroxyanisole. A GLC study suggested that highly polyunsaturated fatty acyl constituents of the microsomal phospholipids might play an important role in epoxidation of the olefinic substrates.

Inhibitory effects of N- and C-terminal truncated Escherichia coli recA gene products on functions of the wild-type recA gene.

The effects of the expression of Escherichia coli truncated RecA protein on the host recA functions were examined. The recA gene on a multicopy plasmid was manipulated to express the truncated RecA protein from its carboxyl (C) and amino (N) terminal ends where a maximum of four extra amino acid residues was added. The regulatory part of the recA gene was substituted by the lacUV5 promoter in the plasmid to facilitate the artificial control of recA expression. Enzyme-linked immunosorbent assay and Western blot analyses revealed great differences in accumulation of the truncated RecA proteins in the cell, depending on the location of the site of truncation. The expression of truncated proteins lacking 62, 77, 93 or 149 amino acid residues from the C-terminal end caused the host recA+ wild-type cell to become sensitive to ultraviolet irradiation and interfered with chromosomal recombination but did not interfere with the induction of lambda prophage. The expression of truncated RecA protein with 25 amino acid residues deleted from the C-terminal end caused the host cell to induce SOS functions constitutively. Truncated RecA proteins with 15 or 28 amino acid residues missing from the N-terminal end severely interfered with all of the host recA functions examined here. The effect of the loss of 41 amino acid residues from the N-terminal end of RecA was significant but less than the effect of proteins lacking 15 or 28 amino acid residues from the N-terminal end. A protein lacking 59 amino acid residues from the N-terminal end showed little interference with any measured recA functions, suggesting that the deletion of the region from around residues 41 to 59, which is rich in hydrophobic side-chains, influenced the ability of the truncated protein to interfere with the functions of wild-type RecA protein. We also constructed a mutant gene with an internal deletion whose product was missing a region from residues 184 to 204. That mutant RecA protein was stably accumulated in the cell. This protein had little effect on the function of host wild-type recA gene product. The possible function of the regions at the N and C termini are discussed.

Daily walking combined with diet therapy is a useful means for obese NIDDM patients not only to reduce body weight but also to improve insulin sensitivity.

OBJECTIVE: To evaluate the effects of walking combined with diet therapy (1,000-1,600 kcal/day) on insulin sensitivity in obese non-insulin-dependent diabetes mellitus (NIDDM) patients. RESEARCH DESIGN AND METHODS: Subjects were divided into two groups: 10 patients were managed by diet alone (group D), and 14 patients were placed in the diet and exercise group (group DE). Group DE was instructed to walk at least 10,000 steps/day on a flat field as monitored by pedometer (19,200 +/- 2,100 steps/day), and group D was told to maintain a normal daily routine (4,500 +/- 290 steps/day). A glucose clamp procedure at an insulin infusion rate of 40 microU.min-2.min-1 was performed before and after the 6- to 8-week training program. Mean serum insulin concentrations ranged from 720 to 790 pmol/l. RESULTS: While body weight (BW) in groups D and DE decreased significantly (P < 0.01) during the study, the amount of BW reduction in group DE was greater than that in group D (7.8 +/- 0.8 vs. 4.2 +/- 0.5 kg, P < 0.01). After training, glucose infusion rate (GIR) and metabolic clearance rate (MCR) in group D did not significantly increase; however, GIR and MCR increased significantly in group DE, from 17.21 +/- 1.11 to 26.09 +/- 1.11 mumol.kg-1.min-1 (P < 0.001) and from 3.0 +/- 0.3 to 5.3 +/- 0.4 ml.kg-1.min-1 (P < 0.001), respectively. The analysis of variance showed significant effects of exercise (time x exercise, P = 0.0005) for the improvement of MCR. Significant correlations were also observed between delta MCR and average steps per day (r = 0.7257, P < 0.005) in group DE. CONCLUSIONS: Walking, which can be safely performed and easily incorporated into daily life, can be recommended as an adjunct therapy to diet treatment in obese NIDDM patients, not only for BW reduction, but also for improvement of insulin sensitivity.

Skin conductance activity after intraventricular administration of 6-hydroxydopa in rats.

Absence of skin conductance response (SCR) and failure of its habituation are psychophysiological signs observed in most schizophrenics. In the present experiments, skin conductance activity was studied in rats before and after intraventricular administration of 6-hydroxydopa (6-OHdopa), a neurotoxin that selectively destroys noradrenaline nerve terminals and induces denervation supersensitivity at the synapse. All intact rats studied (n = 32) showed SCR and its habituation to repeated auditory stimuli (500 Hz, 90 dB, 1 sec, 20 times). They also showed some spontaneous fluctuation (SF) of the skin conductance. In the early stage following the 6-OHdopa (100 micrograms) administration (n = 16), it was noted that the SCR disappeared and the SF were markedly reduced in frequency (p less than 0.001). From the third day to the fourth week after this treatment, there was some recovery of the SF rate, and the SCR tended to reappear with a marked slowing down of its habituation. Eight weeks after the treatment, the majority (11/16) of the 6-OHdopa rats showed habituation failure of the SCR (p less than 0.005); vehicle-treated rats (n = 16) did not show these alterations. Estimation of catecholamine concentration after the experiment confirmed the selective depletion of brain noradrenaline. These results suggest that destruction of the noradrenergic fibers after the 6-OHdopa treatment and denervation supersensitivity which developed later are the cause of the nonresponding and nonhabituating changes of SCR, respectively.

A PCR-mediated method for cloning spot DNA on restriction landmark genomic scanning (RLGS) gel.

A PCR-mediated direct cloning for target spot DNA from RLGS gel has been established. The method consists of PCR amplification of adaptor-ligated spot DNA fragments without excluding similar-sized DNA fragments co-localized on RLGS gel, and following selective ligation with the NotI-dT vector. Applying this method, we have successfully cloned several DNA fragments derived from target spots whose intensities change developmentally due to DNA methylation in the telencephalon of C3H/HeN mice. Since only a few micrograms of total DNA is sufficient for our spot cloning, our method may be highly useful when the total DNA sample prepared for cloning is limited.

Genomic analysis of a NF1-related pseudogene on human chromosome 21.

A neurofibromatosis type-1 (NF1)-related locus on human chromosome 21 has been characterized. A detailed genomic mapping performed by yeast artificial chromosome (YAC) dot-hybridization revealed that the NF1-related locus is close to the sequence-tagged site (STS), D21S329 (G52E12), which is located on the proximal region of 21q11.2. Sequence analysis showed that this locus seemed to be conserved to the NF1 gene only in several partial regions. Two exon-like segments corresponding to exons 8 and 9 of NF1 were found, in addition to two previously found fragments corresponding to exons 7 and 11. Other exon-like segments were not found in the region so far sequenced. Comparing these homologous segments with the NF1 cDNA, a 2-bp deletion appeared in exon 8 of the locus, resulting in the existence of stop codons in all reading frames. In addition, there were no amplified fragments derived from the related locus by reverse transcription-PCR. Thus, our results suggest that the NF1-related locus on chromosome 21 is a nonprocessed pseudogene.

Photogeneration of 3beta-hydroxy-5alpha-cholest-6-ene-5-hydroperoxide in rat skin: evidence for occurrence of singlet oxygen in vivo.

We identified singlet oxygen adduct of cholesterol, 3beta-hydroxy-5alpha-cholest-6-ene-5-hydroperoxide (5alpha-OOH), in skin of rats pretreated with oral doses of pheophorbide a and subsequent visible irradiation, that have been known to induce photosensitive diseases in animals and humans. In a living animal body, this is the first demonstration of presence of 5alpha-OOH, that is known to be formed exclusively by reaction in vitro between singlet oxygen and cholesterol. By the quantitative determination with high performance liquid chromatography equipped with a chemiluminescence detector, we observed time-dependent increase in concentrations of 5alpha-OOH in skin of rats pretreated with oral doses of pheophorbide a and subsequent visible irradiation, suggesting the occurrence of a labile activated oxygen species, singlet oxygen, in this system.

Quantitative determination of cholesterol 5alpha-, 7alpha-, and 7beta-hydroperoxides in rat skin.

An assay method for determination of cholesterol 5alpha-, 7alpha-, and 7beta-hydroperoxides (ChOOHs) in rat skin using high-performance liquid chromatography (HPLC) with a chemiluminescence detector has been developed. In the assay method, free form and free plus ester forms of ChOOHs could be separately determined by HPLC in combination with the treatment of a tissue extract by cholesterol esterase. Lower limits of quantitation for cholesterol 5alpha-, 7alpha-, and 7beta-hydroperoxides were 0.2, 0.1, and 0.5 nmol/g skin, respectively. This assay method showed that (i) good absolute recoveries of ChOOHs from rat skin (80-90% of radiolabeled ChOOHs added to rat skin); (ii) negligible autoxidation of cholesterol caused by the assay procedure (<9.4x10(-5)% of radiolabeled cholesterol added to rat skin); and (iii) good correlation between ChOOHs added to rat skin and ChOOHs determined, indicating this assay method is applicable to quantify ChOOHs in rat skin. By using this assay method, we observed that (i) cholesterol 5alpha-hydroperoxide was detected in skin of rats pretreated with oral doses of pheophorbide a and subsequent visible irradiation; (ii) concentrations of cholesterol 7-hydroperoxides in skin of rats in an ambient light room were not significantly different from those in a dark room for 12 weeks; and (iii) ultraviolet light B irradiation markedly enhanced the concentrations of cholesterol 7-hydroperoxides in the skin of rats.

Increases in cholesterol 7-hydroperoxides in lipids of human skin by sunlight exposure.

Free and ester forms of cholesterol 7alpha- and 7beta-hydroperoxides (Ch 7-OOHs) in skin lipids of humans were separated and determined by high performance liquid chromatography with a chemiluminescence detector. We first demonstrated the presence of Ch 7-OOHs in lipids of human skin. The levels of Ch 7-OOHs found in skin lipids of healthy Japanese volunteers (n = 5) ranged from 2.78 to 25.2 pmol/cm2 skin, indicating large inter-individual differences. However, the intra-individual differences of Ch 7-OOHs levels in skin lipids between right and left arms were less than 25% (-16.4% to 24.0%). Inter-day differences of Ch 7-OOHs in 5 subjects at 1 week interval were also small (-36.7% to 47.7%). Additionally, we investigated effects of sunlight exposure on the levels of Ch 7-OOHs in skin lipids of healthy Japanese volunteers (n = 24). The levels of Ch 7-OOHs in skin lipids significantly increased from 10.0+/-6.7 to 38.9+/-38.0 pmol/cm2 skin by sunlight exposure (10-40 mJ/cm2/min) for 3 h. Therefore, natural sunlight exposure causes lipid peroxidation in skin lipids of humans. These results suggest that the level of Ch 7-OOHs is a good marker for lipid peroxidation in human skin.

An exon-trapping system with a newly constructed trapping vector pEXT2; its application to the proximal region of the human chromosome 21 long arm.

We have developed an exon-trapping system with a newly constructed trapping vector containing multiple cloning sites (designated pEXT2). The system revealed high sensitivity for trapping a control exon from several hundred kbp of DNA. We have applied the system to the cosmid clones located on human chromosome 21p11-q21, and identified two fragments highly homologous to neurofibromatosis 1 (NF1) gene and a clearly transcribed fragment hybridized with approximately 1.6 kb RNA from human brain and human glioblastoma A172 cell.