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61.
Vitiligo is a common depigmentation disorder characterized by the selective loss of melanocytes. In our daily clinic experience, we noticed that the skin tightness of hypopigmented lesions would be more evident in comparison to that of uninvolved perilesional skin in vitiligo patients. Therefore, we hypothesized that collagen homeostasis might be maintained in vitiligo lesions, irrespective of the substantial excessive oxidative stress that occurs in association with the disease. We found that the expression levels of collagen-related genes and anti-oxidative enzymes were upregulated in vitiligo-derived fibroblasts. Abundant collagenous fibers were observed in the papillary dermis of vitiligo lesions in comparison to uninvolved perilesional skin by electron microscopy. The production of matrix metalloproteinases that degraded collagen fibers was suppressed. The deposition of acrolein adduct protein, which is a product of oxidative stress, was significantly reduced in vitiligo dermis and fibroblasts. As part of the mechanism, we found upregulation of the NRF2 signaling pathway activity, which is an important defense system against oxidative stress. Taken together, we demonstrated that the anti-oxidative action and collagen production were upregulated and that the collagen degeneration was attenuated in vitiligo dermis. These new findings may provide important clues for the maintenance of antioxidant ability in vitiligo lesions.  相似文献   
62.
Staphylococcus warneri M exhibited extracellular lipase activity. By zymogram analysis of extracellular proteins, multiple bands were detected and the profiles changed depending on the bacterial growth phase. N-terminal amino acid sequences of three bands (N1-N3) were determined. From the genome library of S. warneri M whole DNA, the gene-directing lipase activity (named gehC(WM)) was cloned and characterized. The gehC(WM )gene encoded a protein (GehC(WM)), whose calculated molecular mass was 83.4 kDa, and the sequence was similar to the other staphylococcal lipases. Though two lipases have been known from S. warneri 863, GehC(WM) differs from both of them, indicating that this enzyme is the third extracellular lipase of the S. warneri strain. The N-terminal sequences of the N1-N3 polypeptides completely coincided with the deduced amino acid sequences in GehC(WM). GehC(WM) was predicted to be a prepro-protein. In vitro processing and protein sequencing suggested that pro-GehC(WM) is possibly processed by extracellular glutamyl endopeptidase, PROM. Inductively coupled plasma-atomic emission spectrometer analysis showed that purified his-tagged mature GehC(WM) possessed zinc ion. A gehC(WM) knockout mutant was constructed by insertion of an erythromycin resistance gene into the gehC(WM). Zymogram and immunoblot analyses of the gehC(WM )mutant indicated that GehC(WM) was a major extracellular lipase of S. warneri M.  相似文献   
63.
Guanidinoethanesulfonic acid (GES) is known to induce convulsive seizures when administered intracisternally to rabbits and cats. The effects of GES on behavior, electroencephalographic recording and brain monoamine levels were examined in mice. When GES (900 nmol) was intraventricularly injected into mice, focal clonic movements of the face, vibrissae and ears together with twitching of the limbs were observed 0.5–1 min after the injection. Hypersensitivity was observed up to 7 min after the injection, after which the mice behaved normally. GES also induced sporadic spike discharges on electrocorticogram. The levels of 5-hydroxytryptamine (5-HT) of the GES-injected mice were lower than those of the saline-injected mice in the hippocampus, diencephalon, pons-medulla oblongata and cerebellum 5 min after the injection. No changes in the norepinephrine or dopamine levels were found after the GES injection. The level of 5-hydroxyindoleacetic acid increased in the striatum and cerebellum 5 min after the GES injection. These results suggest that GES-induced convulsive activities enhance the serotonergic neuroactivity in order to suppress the convulsions.  相似文献   
64.
A number of factors influencing microspore embryogenesis and plant regeneration were examined in five subspecies (rapa, oleifera, niposinica, perviridis, broccoletto) of B. rapa. Addition of 6-benzylaminopurine (BA) in 1/2 NLN-10 medium improved the embryo yield by 2?C12 fold. Addition of activated charcoal (AC) in the medium was not effective for microspore embryogenesis. Moreover, AC canceled the positive effect of BA, when the medium containing both BA and AC was used. Of 24 genotypes examined for microspore embryogenesis, 22 genotypes of all five subspecies produced embryos ranging from 0.02 to 15.0 per 2?×?105 microspores, but two genotypes were not responsive. Low temperature pretreatment of flower buds significantly improved the microspore embryogenesis. When cotyledonary embryos were subcultured on a filter paper placed on top of 0.8?% agar-solidified B5-2 medium and 1.6?% agar B5-2 medium, plant regenerations were increased 4?C8 fold compared to 0.8?% agar medium. The ploidy levels of regenerated plants in three genotypes were determined by flow cytometry, revealing that 66?C100?% of them were diploid. The results enable the advancement of breeding programs and genetic studies in B. rapa.  相似文献   
65.
Age-related macular degeneration, diabetic retinopathy, and retinal vein occlusions are complicated by neovascularization and macular edema. Multi-targeted kinase inhibitors that inhibit select growth factor receptor tyrosine kinases and/or components of their down-stream signaling cascades (such as Src kinases) are rationale treatment strategies for these disease processes. We describe the discovery and characterization of two such agents. TG100572, which inhibits Src kinases and selected receptor tyrosine kinases, induced apoptosis of proliferating endothelial cells in vitro. Systemic delivery of TG100572 in a murine model of laser-induced choroidal neovascularization (CNV) caused significant suppression of CNV, but with an associated weight loss suggestive of systemic toxicity. To minimize systemic exposure, topical delivery of TG100572 to the cornea was explored, and while substantial levels of TG100572 were achieved in the retina and choroid, superior exposure levels were achieved using TG100801, an inactive prodrug that generates TG100572 by de-esterification. Neither TG100801 nor TG100572 were detectable in plasma following topical delivery of TG100801, and adverse safety signals (such as weight loss) were not observed even with prolonged dosing schedules. Topical TG100801 significantly suppressed laser-induced CNV in mice, and reduced fluorescein leakage from the vasculature and retinal thickening measured by optical coherence tomography in a rat model of retinal vein occlusion. These data suggest that TG100801 may provide a new topically applied treatment approach for ocular neovascularization and retinal edema.  相似文献   
66.
Genome duplications increase genetic diversity and may facilitate the evolution of gene subfunctions. Little attention, however, has focused on the evolutionary impact of lineage-specific gene loss. Here, we show that identifying lineage-specific gene loss after genome duplication is important for understanding the evolution of gene subfunctions in surviving paralogs and for improving functional connectivity among human and model organism genomes. We examine the general principles of gene loss following duplication, coupled with expression analysis of the retinaldehyde dehydrogenase Aldh1a gene family during retinoic acid signaling in eye development as a case study. Humans have three ALDH1A genes, but teleosts have just one or two. We used comparative genomics and conserved syntenies to identify loss of ohnologs (paralogs derived from genome duplication) and to clarify uncertain phylogenies. Analysis showed that Aldh1a1 and Aldh1a2 form a clade that is sister to Aldh1a3-related genes. Genome comparisons showed secondarily loss of aldh1a1 in teleosts, revealing that Aldh1a1 is not a tetrapod innovation and that aldh1a3 was recently lost in medaka, making it the first known vertebrate with a single aldh1a gene. Interestingly, results revealed asymmetric distribution of surviving ohnologs between co-orthologous teleost chromosome segments, suggesting that local genome architecture can influence ohnolog survival. We propose a model that reconstructs the chromosomal history of the Aldh1a family in the ancestral vertebrate genome, coupled with the evolution of gene functions in surviving Aldh1a ohnologs after R1, R2, and R3 genome duplications. Results provide evidence for early subfunctionalization and late subfunction-partitioning and suggest a mechanistic model based on altered regulation leading to heterochronic gene expression to explain the acquisition or modification of subfunctions by surviving ohnologs that preserve unaltered ancestral developmental programs in the face of gene loss.  相似文献   
67.
β-Glucosidase hydrolyzing cellobiose was extracted from Aureobasidium sp ATCC 20524 and purified to homogeneity. The molecular mass was estimated to be about 331 kDa. The enzyme contained 26.5% (w/w) carbohydrate. The optimum pH and temperature for the enzyme reaction were pH 4 and 80°C, respectively. The enzyme was stable at a wide range of pH, 2.2–9.8, after 3 h and at 75°C for 15 min. The kinetic parameters were determined. The enzyme was relatively stable against typical organic enzyme inhibitors. The enzyme also hydrolyzed gentiobiose, p-nitrophenyl-β-glucoside and salicin. Received 05 November 1998/ Accepted in revised form 14 February 1999  相似文献   
68.
Iron deficiency without anemia (IDNA), the most prevalent nutritional deficiency worldwide, affects young women of reproductive age. This study aimed to elucidate the relationship between IDNA and mental and somatic symptoms including anger and fatigue using the Japanese version of the Cornell Medical Index Health Questionnaire (CMI–J). Data regarding demographic characteristics, anthropometry, hematological, and biochemical indices of the iron status, frequencies of selected food intakes assessed by self-administered food frequency questionnaires (FFQs), frequencies of nonspecific symptoms, and grades of neurotic tendencies assessed by CMI–J were collected from 76 young women aged 18–22 years living in the metropolitan area of Tokyo, Japan. The subjects were classified as having IDNA (hemoglobin (Hb)?≥?12 g/dL and serum ferritin?<?20 ng/mL; n?=?29), having iron deficiency anemia (IDA) (Hb?<?12 g/dL and serum ferritin?<?20 ng/mL; n?=?10), or having a normal iron status (Hb?≥?12 g/dL and serum ferritin?≥?20 ng/mL; n?=?36). One subject was excluded from the analyses because of Hb?<?12 g/dL and serum ferritin?≥?20 ng/mL. Fisher’s protected least significant difference and the Dwass–Steel–Chritchlow–Fligner multiple comparison tests were used to compare the data of the three groups. P values <0.05 were considered significant. Sections M–R (mental complaints) were significantly higher in the IDNA subjects than in the normal subjects. No significant difference in CMI scores was found between the normal and IDA subjects. Sections I (fatigability), Q (anger), and R (tension) were significantly higher in the IDNA subjects than in the normal subjects, regardless of no significant differences between the normal and IDA subjects in those sections. Young women with IDNA demonstrated a significantly higher proportion of neurotic tendencies (grades II–IV). The intake frequency score of canned or bottled green tea fortified with vitamin C was significantly higher in the IDNA subjects than the IDA subjects. The findings suggest that IDNA may be a risk factor for anger, fatigue, and tension in women of childbearing age.  相似文献   
69.
“Bulk density” and “dry-matter content” are useful indices of dry-matter accumulation in plant organs. A theoretical equation describing the relationship between these two indices was put forward. To examine the reliability of this equation, the seasonal changes of these two indices were investigated in the leaves and stems of different ages ofAucuba japonica. In each organ both indices varied seasonally almost parallel to each other, but the seasonal changes of dry-matter content were less obvious than those of bulk density. The observed bulk density was always larger than that calculated from the observed dry-matter content by the theoretical equation. A drying experiment showed that this discrepancy was caused by the decrement of the volume of the plant material by water loss during the period from the weight measurement to the volume measurement. When the water loss was negligible, the equation described well the relationships between the two indices of the experimental materials. It was also shown that this equation was useful for the estimation of the amount of air space in plant materials.  相似文献   
70.
To correlate rat genetic linkage maps with cytogenetic maps, we localized 25 new cosmid-derived simple sequence length polymorphism (SSLP) markers and 14 existing genetic markers on cytogenetic bands of chromosomes, using fluorescence in situ hybridization (FISH). Next, a total of 58 anchor loci, consisting of the 39 new and 19 previously reported ones, were integrated into the genetic linkage maps. Since most of the new anchor loci were developed to be localized near the terminals of the genetic or cytogenetic maps for each chromosome, the orientation and coverage of the whole genetic linkage maps were determined or confirmed with respect to the cytogenetic maps. Thus, we provide here a new base for rat genetic maps. Received: 9 September 1997 / Accepted: 11 November 1997  相似文献   
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