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51.
In this article, we describe a novel autosomal recessive ichthyosis with hypotrichosis syndrome, characterized by congenital ichthyosis associated with abnormal hair. Using homozygosity mapping, we mapped the disease locus to 11q24.3-q25. We screened the ST14 gene, which encodes matriptase, since transplantation of skin from matriptase(-/-)-knockout mice onto adult athymic nude mice has been shown elsewhere to result in an ichthyosislike phenotype associated with almost complete absence of erupted pelage hairs. Mutation analysis revealed a missense mutation, G827R, in the highly conserved peptidase S1-S6 domain. Marked skin hyperkeratosis due to impaired degradation of the stratum corneum corneodesmosomes was observed in the affected individuals, which suggests that matriptase plays a significant role in epidermal desquamation.  相似文献   
52.
The purpose of this study was to compare the development of trunk musculature among Elite, Sub-elite, and Elite junior wrestlers. The performance level of these groups, ordered highest to lowest, is as follows: Elite (n = 20), Sub-elite (n = 25), and Elite junior (n = 39). A magnetic resonance imaging device was used to measure the cross-sectional area (CSA) of the trunk muscles. The whole trunk muscle cross-sectional area (t-MCSA) of the Elite group was significantly larger than that of the Elite junior group (p < 0.05). The rectus abdominis muscle CSA of the Elite group was significantly larger than that of the Elite junior group (p < 0.01). The psoas major muscle CSA of the Elite group was significantly larger than that of the Elite junior group (p < 0.05). There were no significant differences in the CSA of any of the trunk muscles between the Elite and Sub-elite groups. In conclusion, compared with Elite junior wrestlers, it is conceivable that a greater CSA of trunk flexors of Elite wrestlers is one factor which supports increased performance.  相似文献   
53.
In the past decades, the function of the Wnt canonical pathway during embryogenesis has been intensively investigated; however, little survey of neonatal and adult tissues has been made, and the role of this pathway remains largely unknown. To investigate its role in mature tissues, we generated two new reporter transgenic mouse lines, ins-TOPEGFP and ins-TOPGAL, that drive EGFP and beta-galactosidase expression under TCF/beta-catenin, respectively. To obtain the accurate expression pattern, we flanked these transgenes with the HS4 insulator to reduce chromosomal positional effects. Analysis of embryos showed that the reporter genes were activated in regions where canonical Wnt activity has been implicated. Furthermore, their expression patterns were consistent in both lines, indicating the accuracy of the reporter signal. In the neonatal brain, the reporter signal was detected in the mesencephalon and hippocampus. In the adult mice, the reporter signal was found in the mature pericenteral hepatocytes in the normal liver. Furthermore, during inflammation the number of T cells expressing the reporter gene increased in the adult spleen. Thus, in this research, we identified two organs, i.e., the liver and spleen, as novel organs in which the Wnt canonical signal is in motion in the adult. These transgenic lines will provide us broader opportunities to investigate the function of the Wnt canonical pathway in vivo.  相似文献   
54.
55.
Five carboxin-resistant mutants from Aspergillus oryzae were characterized by the sensitivities of their mycelial growth and succinate dehydrogenase (SDH) activity to carboxin and three related fungicides. Despite a significant resistance to carboxin, exhibited by all the mutants, their patterns of sensitivity to the other fungicides was distinct. This provides clues to the molecular interaction between SDH and these fungicides.  相似文献   
56.
Seed dormancy is an adaptive mechanism and an important agronomic trait. Temperature during seed development strongly affects seed dormancy in wheat (Triticum aestivum) with lower temperatures producing higher levels of seed dormancy. To identify genes important for seed dormancy, we used a wheat microarray to analyze gene expression in embryos from mature seeds grown at lower and higher temperatures. We found that a wheat homolog of MOTHER OF FT AND TFL1 (MFT) was upregulated after physiological maturity in dormant seeds grown at the lower temperature. In situ hybridization analysis indicated that MFT was exclusively expressed in the scutellum and coleorhiza. Mapping analysis showed that MFT on chromosome 3A (MFT-3A) colocalized with the seed dormancy quantitative trait locus (QTL) QPhs.ocs-3A.1. MFT-3A expression levels in a dormant cultivar used for the detection of the QTL were higher after physiological maturity; this increased expression correlated with a single nucleotide polymorphism in the promoter region. In a complementation analysis, high levels of MFT expression were correlated with a low germination index in T1 seeds. Furthermore, precocious germination of isolated immature embryos was suppressed by transient introduction of MFT driven by the maize (Zea mays) ubiquitin promoter. Taken together, these results suggest that MFT plays an important role in the regulation of germination in wheat.  相似文献   
57.
Aberrant reprogramming of donor somatic cell nuclei may result in many severe problems in animal cloning. The inability to establish functional interactions between donor nucleus and recipient mitochondria is also likely responsible for such a developmental deficiency. However, detailed knowledge of protein expression during somatic cell nuclear transfer (SCNT) in cattle is lacking. In the present study, variations in mitochondrial protein levels between SCNT‐derived and control cattle, and from calves derived by artificial insemination were investigated. Mitochondrial fractions were prepared from frozen liver samples and subjected to two‐dimensional (2‐D) fluorescence differential gel electrophoresis (DIGE) using CyDye? dyes. Protein expression changes were confirmed with a volume ratio greater than 2.0 (P < 0.05). 2D‐DIGE analysis revealed differential expression of three proteins for SCNT cattle (n = 4) and seven proteins for SCNT calves (n = 6) compared to controls (P < 0.05). Different protein patterning was observed among SCNT animals even if animals were generated from the same donor cell source. No differences were detected in two of the SCNT cattle. Moreover, there was no novel protein identified in any of the SCNT cattle or calves. In conclusion, variation in mitochondrial protein expression concentrations was observed in non‐viable, neonatal SCNT calves and among SCNT individuals. This result implicates mitochondrial‐related gene expression in early developmental loss of SCNT embryos. Comparative proteomic analysis represents an important tool for further studies on SCNT animals. Mol. Reprod. Dev. 78:263–273, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
58.
In the present study, we investigated the effects of inhibition of the caudal ventrolateral medulla (CVLM) with the GABA(A) agonist muscimol combined with the blockade of glutamatergic mechanism in the nucleus of the solitary tract (NTS) with kynurenic acid (kyn) on mean arterial pressure (MAP), heart rate (HR), and regional vascular resistances. In male Holtzman rats anesthetized intravenously with urethane/chloralose, bilateral injections of muscimol (120 pmol) into the CVLM or bilateral injections of kyn (2.7 nmol) into the NTS alone increased MAP to 186 +/- 11 and to 142 +/- 6 mmHg, respectively, vs. control: 105 +/- 4 mmHg; HR to 407 +/- 15 and to 412 +/- 18 beats per minute (bpm), respectively, vs. control: 352 +/- 12 bpm; and renal, mesenteric and hindquarter vascular resistances. However, in rats with the CVLM bilaterally blocked by muscimol, additional injections of kyn into the NTS reduced MAP to 88 +/- 5 mmHg and mesenteric and hindquarter vascular resistances below control baseline levels. Moreover, in rats with the glutamatergic mechanisms of the NTS blocked by bilateral injections of kyn, additional injections of muscimol into the CVLM also reduced MAP to 92 +/- 2 mmHg and mesenteric and hindquarter vascular resistances below control baseline levels. Simultaneous blockade of NTS and CVLM did not modify the increase in HR but also abolished the increase in renal vascular resistance produced by each treatment alone. The results suggest that important pressor mechanisms arise from the NTS and CVLM to control vascular resistance and arterial pressure under the conditions of the present study.  相似文献   
59.
In recent years, circadian rhythm sleep disorders in humans have been increasing. Clinical features characteristic of this disorder are well known, but the specific causes remain unknown. However, various derangements of circadian expression of the clock gene are a probable cause of this disease. We have attempted to elucidate the relationship between the expression of the clock genes in whole blood cells and the clinical features characteristic of this disorder. In this study, we indicate the daily expression of clock genes period (Per) 1, 2, 3, Bmal1, and Clock in whole blood cells in 12 healthy male subjects. The peak phase of Per1, Per2, and Per3 appeared in the early morning, whereas that of Bmal1 and Clock appeared in the midnight hours. Furthermore, in one patient case with circadian rhythm sleep disorder, we observed variations of the peak phase in clock genes by treatments such as light therapy, exercise therapy, and medicinal therapy. This study suggested that the monitoring of human clock genes in whole blood cells, which may be functionally important for the molecular control of the circadian pacemaker as well as in suprachiasmatic nucleus, might be useful to evaluate internal synchronization.  相似文献   
60.
Nineteen carotenoids were identified in extracts of petals of orange- and yellow-flowered cultivars of calendula (Calendula officinalis L.). Ten carotenoids were unique to orange-flowered cultivars. The UV-vis absorption maxima of these ten carotenoids were at longer wavelengths than that of flavoxanthin, the main carotenoid of calendula petals, and it is clear that these carotenoids are responsible for the orange color of the petals. Six carotenoids had a cis structure at C-5 (C-5'), and it is conceivable that these (5Z)-carotenoids are enzymatically isomerized at C-5 in a pathway that diverges from the main carotenoid biosynthesis pathway. Among them, (5Z,9Z)-lycopene (1), (5Z,9Z,5'Z,9'Z)-lycopene (3), (5'Z)-gamma-carotene (4), and (5'Z,9'Z)-rubixanthin (5) has never before been identified. Additionally, (5Z,9Z,5'Z)-lycopene (2) has been reported only as a synthesized compound.  相似文献   
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