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71.
In this study, we investigated the effects of N-acetylserotonin (NAS) on cell proliferation and neuroblast differentiation in the mouse dentate gyrus using anti-Ki67 and anti-doublecortin (DCX) antibodies. Ki67 is expressed in the nucleus or on the surface of chromosomes during all of the active phases of the cell cycle, and DCX is expressed in neuronal precursor cells as well as in immature neurons. At 17 weeks of age, 20 mg/kg of NAS or the same volume of vehicle was intraperitoneally administered once a day for 3 weeks. The animals were sacrificed 2 hr after the last vehicle or NAS treatment. NAS treatment significantly increased the number of Ki67-positive nuclei and DCX-immunoreactive neuroblasts with well-developed dendrites (tertiary dendrites) compared to the vehicle-treated group. However, the number of DCX-immunoreactive neuroblasts without tertiary dendrites was not changed. The administration of NAS also significantly increased the protein levels of brain-derived neurotrophic factor (BDNF) in the dentate gyrus. This result suggests that NAS significantly promotes cell proliferation and the number of differentiating neuroblasts with tertiary dendrites through an increase in BDNF levels in the mouse dentate gyrus.  相似文献   
72.
Polylactic acid (PLA) has received considerable attention as a biomass material for the textile industry. To use a PLA fabric in the textile industry, suitable postprocessing that can promote hydrophilicity of such fabrics is required. Here, hydrolytic action of a proteolytic enzyme (alcalase from Bacillus licheniformis) on PLA fibers was evaluated. In addition, the effects of an additive on the enzymatic hydrolysis were analyzed. The results revealed that the optimal enzymatic-hydrolysis conditions for this alcalase are pH 9.5, temperature 60 °C, enzyme concentration 50 % on weight of fabric (owf), and Lcysteine concentration of 3 mM. PLA fabrics were hydrolyzed effectively, however; there was no damage to these fabrics judging by tensile strength and surface observations. X-ray diffractometry identified a new peak (at 2θ=18.5 °), implying a morphological change caused by the treatment. Moreover, hydrophilic properties such as moisture regain and dyeing properties were enhanced by this proteolytic enzymatic hydrolysis. Therefore, according to this study, enzymatic hydrolysis is a suitable finishing method for improvement of hydrophilicity of PLA fabrics.  相似文献   
73.
beta-Glucan extracted from oats was subjected to reductive amination, producing a cationic beta-glucan derivative of which physiological properties were characterized. The degree of substitution was obtained from elemental analysis, which was 0.48. In addition, the distribution of amino groups in the beta-glucan derivative was investigated by FT-IR analysis. In vitro bile acid binding capacity of the aminated beta-glucan was examined, showing significantly higher bile acid binding activity than native beta-glucan. Moreover, the beta-glucan derivative showed pronounced antimicrobial effects against Escherichia coli and Bacillus subtilis, and ACE (angiotensin-converting enzyme) inhibition activities which were dependent on its concentration. Furthermore, bronchoalveolar lavage (BAL) experiments demonstrated that the beta-glucan derivative stimulated the synthesis of nitric oxide. The improved functionalities of the derivative could be explained by its polycationic characteristics.  相似文献   
74.
In a male Korean native calf 14 days of age, polymelia (notomelia) was observed macroscopically and radiographically. External features included two normal forelimbs, two normal hindlimbs and two undeveloped extra forelimbs. The extra forelimbs were attached to the caudal regions of the right scapula and devoid of muscular tissues. In the extra forelimbs, a scapula-like bone formed a joint with the incompletely duplicated humerus. The humerus fused with the incompletely duplicated radius. The ulna, carpal bones, metacarpal bones and phalanges were completely duplicated. But one set of the duplicated carpal bones consisted of five bones: radial, accessory, fourth carpal, fused second and third carpal, and fused ulnar and intermediate carpal bones. The hoof and the rudimentary hoof of accessory digit were duplicated.  相似文献   
75.
A recently designed single-crystal surface calorimeter has been deployed to measure the energy difference between two solid surface structures. The clean Pt{100} surface is reconstructed to a stable phase in which the surface layer of platinum atoms has a quasi-hexagonal structure. By comparison of the heats of adsorption of CO and of C(2)H(4) on this stable Pt{100}-hex phase with those on a metastable Pt{100}-(1x1) surface, the energy difference between the two clean phases was measured as 20 +/- 3 and 25 +/- 3 kilojoules per mole of surface platinum atoms.  相似文献   
76.
Variants in the FTO (fat mass and obesity associated) gene are associated with increased body mass index in humans. Here, we show by bioinformatics analysis that FTO shares sequence motifs with Fe(II)- and 2-oxoglutarate-dependent oxygenases. We find that recombinant murine Fto catalyzes the Fe(II)- and 2OG-dependent demethylation of 3-methylthymine in single-stranded DNA, with concomitant production of succinate, formaldehyde, and carbon dioxide. Consistent with a potential role in nucleic acid demethylation, Fto localizes to the nucleus in transfected cells. Studies of wild-type mice indicate that Fto messenger RNA (mRNA) is most abundant in the brain, particularly in hypothalamic nuclei governing energy balance, and that Fto mRNA levels in the arcuate nucleus are regulated by feeding and fasting. Studies can now be directed toward determining the physiologically relevant FTO substrate and how nucleic acid methylation status is linked to increased fat mass.  相似文献   
77.
Astaxanthin, a carotenoid, has antioxidant activity as well as many positive effects, such as anticancer and anti-inflammatory effects. We performed a randomized, double-blind, placebo-controlled study to investigate the effects of astaxanthin on lipid profiles and oxidative stress in overweight and obese adults in Korea. In total, 27 subjects with body mass index >25.0 kg/m2 were enrolled and randomly assigned into two groups administered astaxanthin or placebo capsules for 12 weeks. Total cholesterol, triglycerides, high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, apolipoprotein A1 (ApoA1), and apolipoprotein B (ApoB) were measured before and after intervention. Malondialdehyde (MDA), isoprostane (ISP), superoxide dismutase (SOD), and total antioxidant capacity (TAC), as oxidative stress biomarkers, were measured at baseline and at 4, 8, and 12 weeks after intervention. LDL cholesterol and ApoB were significantly lower after treatment with astaxanthin, compared with the start of administration, whereas none of the lipid profiles was changed in the placebo group. At the baseline, all four biomarkers were not significantly different between the two groups. Compared with the placebo group, MDA and ISP were significantly lower, but TAC was significantly higher in the astaxanthin group at 12 weeks. These results suggest that supplementary astaxanthin has positive effects by improving the LDL cholesterol, ApoB, and oxidative stress biomarkers.  相似文献   
78.
We have manufactured poly(vinylidene fluoride) (PVDF)-based nanocomposite films with different graphene contents of 0.1~10.0 wt% by ultrasonicated solution-mixing and melt-compression. As a reinforcing nanofiller, graphene sheets are prepared by rapid thermal expansion of graphite oxide, which are from the oxidation of natural graphite flakes. Graphene sheets are characterized to be well exfoliated and dispersed in the nanocomposite films. X-ray diffraction data confirm that the α-phase crystals of PVDF are dominantly developed in the nanocomposite films during the meltcrystallization. DSC cooling thermograms show that the graphene sheets serve as nucleating agents for the PVDF α-form crystals. Thermal stability of the nanocomposite films under oxygen gas atmosphere is noticeably improved, specifically for the nanocomposite with 1.0 wt% graphene. Electrical volume resistivity of the nanocomposite films is substantially decreased from ~1014 to ~106 W cm, especially at a critical graphene content between 1.0 and 3.0 wt%. In addition, mechanical storage modulus is highly improved with increasing the graphene content in the nanocomposite films. The increment of the storage modulus for the nanocomposite film at 30 °C with increasing the graphene content is analyzed by adopting the theoretical model proposed by Halpin and Tsai.  相似文献   
79.
Mechanical properties and the long-term degradation properties of the recycled PET yarns are typically lower than the virgin PET yarns due to the contaminants coming from non-PET bottles, labels and caps etc. For environmental reasons, recycling of post-consumer polyester bottles into textile fibers has become commercially attractive. We studied mechanical and chemical recycling processes and examined their effects on yarn properties such as tensile properties, thermal characteristics, hydrolysis and photo-degradation. It was found that the virgin and the chemical recycled yarns with sufficient purification show similar processability, physical and mechanical properties, and long-term degradation behavior. The results provide useful information on recycled PET yarns for processability and serviceability for the high-end use.  相似文献   
80.
Seoul National University (SNU) miniature pigs represent a closed colony with 24 founder pigs and a well preserved pedigree. Characterization using mRNA sequence analysis was conducted for 6 swine leukocyte antigen (SLA) loci in parental or founder pigs, and 17 defined alleles were detected. Based on these complete coding sequences, 17 sequence specific primers (SSPs) were designed for polymorphic sites. To validate the specificity of each allele SSP, the PCR‐SSP was conducted with defined allele clones as templates. PCR‐SSP was conducted with the hot start polymerase and touch‐down PCR. The parental or found SNU miniature pigs showed overall SLA class I and II heterozygotes. Using the established PCR‐SSP method, we conducted SLA typing for breeding stock including 2 pedigreed pigs and identified the novel SLA class II homozygote haplotye (DRA*0201, DRB1*0403, DQA*0102 and DQB1*0701) and 2 SLA homozygote pig lines: SLA class I Hp‐3.0 and class II Hp‐0.3, and SLA class I Hp‐2.0 and class II Hp‐0.2. We thought that our PCR‐SSP SLA typing method could be applicable for new SLA homozygote line establishment by assignment and scheduled breeding.  相似文献   
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