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931.
Parkinson’s disease is the second most common neurodegenerative disorder with selective and progressive decline of nigral dopaminergic neurons. Hypericum perforatum L. (H. perforatum, St. John’s wort) has been traditionally used for management of different disorders, especially mild-to-moderate depression. This study was conducted to evaluate the effect of H. perforatum extract against unilateral striatal 6-hydroxydopamine (6-OHDA) toxicity and to unmask some involved mechanisms. Intrastriatal 6-OHDA-lesioned rats were treated with H. perforatum hydroalcoholic extract at a dose of 200 mg/kg/day started 1 week pre-surgery for 1 week post-surgery. The extract attenuated apomorphine-induced rotational behavior, decreased the latency to initiate and the total time on the narrow beam task, lowered striatal level of malondialdehyde and enhanced striatal catalase activity and reduced glutathione content, normalized striatal expression of glial fibrillary acidic protein, tumor necrosis factor α with no significant effect on mitogen-activated protein kinase, lowered nigral DNA fragmentation, and prevented damage of nigral dopaminergic neurons with a higher striatal tyrosine hydroxylase immunoreactivity. These findings reveal the beneficial effect of H. perforatum via attenuation of DNA fragmentation, astrogliosis, inflammation, and oxidative stress.  相似文献   
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BackgroundMetabolic abnormalities that lead to type 2 diabetes mellitus begin in early childhood.ObjectivesWe investigate whether common genetic variants identified in adults have an effect on glucose in early life.Methods610 newborns, 463 mothers, and 366 fathers were included in the present study. Plasma glucose and anthropometric characteristics were collected at birth, 3, and 5 years. After quality assessment, 37 SNPs, which have demonstrated an association with fasting plasma glucose at the genome-wide threshold in adults, were studied. Quantitative trait disequilibrium tests and mixed-effects regressions were conducted to estimate an effect of the SNPs on glucose.ResultsRisk alleles for 6 loci increased glucose levels from birth to 5 years of age (ADCY5, ADRA2A, CDKAL1, CDKN2A/B, GRB10, and TCF7L2, 4.85x10-3P ≤ 4.60x10-2). Together, these 6 SNPs increase glucose by 0.05 mmol/L for each risk allele in a genotype score (P = 6.33x10-5). None of the associations described in the present study have been reported previously in early childhood.ConclusionOur data support the notion that a subset of loci contributing to plasma glucose variation in adults has an effect at birth and in early life.  相似文献   
935.
As an ancient disease, tuberculosis (TB) is a major global health threat. Therefore, there is an urgent need for an effective and safe anti-TB vaccine. In the current study, a delivery system of Fc domain of mouse IgG2a and early secreted antigenic target protein 6 (ESAT-6) was evaluated for the selective uptake of antigens by antigen-presenting cells (APCs). Thus, it was based on the immunogenicity of a fusion protein. The study was initiated by the transfer of recombinant expression vectors of pPICZαA-ESAT-6:Fcγ2a and pPICZαA-ESAT-6: His into Pichia pastoris (P. pastoris). Recombinant proteins were assessed for immunogenicity following the immunoblotting analysis. High levels of IFN-γ and IL-12 were produced to induce Th1-type cellular responses through vaccination with both recombinant proteins [ESAT-6:Fcγ2a (EF) and ESAT-6:His (EH)]. The Fc-tagged recombinant protein induced more effective Th1-type cellular responses with a low increment in IL-4 compared to PBS, BCG, and EH groups. Although in all the immunized groups, the ratio of IFN-γ/IL-4 was in favor of Th1 responses, the highest Th1/Th2 balance was observed in EF immunized group. Fc fragment of mouse IgG2a may induce a selective uptake of APCs towards the cross-presentation and formation of Th1 responses in favor of an appropriate protective anti-tuberculosis reaction. Thus, further research on Fc-fusion proteins is required to develop Fc-based TB vaccines.  相似文献   
936.
Microalgae have been used commercially as a feedstock for the production of high-value compounds, pigments, cosmetics, and nutritional supplements. In addition, because of their rapid growth rates, high photosynthetic efficiency, and high lipid and protein content, commodity products including biodiesel, feed supplements, and polyunsaturated fatty acids derived from algal biomass are of current interest. Since microalgae lack non-photosynthetic structures and float in water, they do not need massive amounts of structural cellulose found in land plants. Thus, under optimal culture conditions, some oleaginous species can allocate up to 70 % of their biomass to lipids. Lipid production and its regulation in microalgae are species-specific and influenced by environmental conditions. Various strategies have been developed to improve lipid productivity and fatty acid composition to meet specific production goals. Manipulation of physiochemical parameters, trophic modes, and nutrient levels, known as process engineering, is a simple approach that leads to desired alterations in the biochemical composition of algal biomass, including lipid quantity and quality. In this paper, we review the effects of manipulating biochemical parameters such as necessary nutrients (C, N, P, S, Fe, and Si), NaCl concentration, and pH of culture medium to optimize lipid content and profile in some algae strains with commercial potential.  相似文献   
937.
UV–Vis and electronic circular dichroism (ECD) spectroscopy, complemented with Density Functional Theory (DFT) calculations, were used to elucidate the structural diversities of three multidentate nitrogen donor ligands and two associated copper complexes in solution directly. The three chiral salen ligands all consist of trans‐cyclohexane‐1,2‐diamine as a chiral scaffold and also of pyridine rings as chromophores, differing only in the linking groups between the two functional groups mentioned above. Very different ECD intensities and somewhat different ECD patterns were observed for these ligands and satisfactorily interpreted theoretically. For the geometry optimization and spectral simulation of the open‐shell metal complexes, the LANL2DZ basis set with effective core potential for the Cu and Cl atoms and pure cc‐pVTZ for the rest of the atoms was utilized. The performance of the same calculations with the polarization functions (f,g) from the cc‐pVTZ basis added to the LANL2DZ basis was compared. While the three ligands exhibit different conformational flexibility, the associated copper complexes show great rigidity imposed by the metal–ligand coordination, taking on a single structure in each case. In addition, dispersion interactions were shown to change the conformational stability ordering of the ligands noticeably and to exert considerable influence on the simulated UV–Vis and ECD spectra. Chirality 28:545–555, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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Bamboo is grown sporadically in the north of Iran and is confined to very limited areas. The history of growing bamboo was to some extent simultaneous with the entrance, commencement, and growth of the tea industry in the north about a century ago. The bamboo was used for making baskets to transfer the harvested tea foliage from farm to the factory and other linked functions. A main area allocated for bamboo growing is located in Lahidjan Agricultural Research Station (LARS) in the north of Iran, where several species of bamboo were cultivated in an area of 5 ha. The species include five species of Phyllostachys (viz., P. aurea, P. bambusoides, P. decora, P. nigra, P. vivax) and one species of Arundinaria gigantean, Pleioblastus fortune, and Semiarundinaria fastuosa; however, only P. aurea and P. nigra have been precisely identified. A survey on plant parasitic nematodes associated with bamboo mainly on P. nigra in LARS revealed second-stage juveniles of cyst forming nematode in soil samples. Further analysis of root and soil samples led to recovery of a cyst nematode belonging to the genus Heterodera and the Afenestrata group. Cysts, vulval cone, and second-stage juveniles were studied for morphological and morphometric features. The classical identification was followed by amplification of the ribosomal RNA-ITS region and the D2-D3 expansion segments of 28S large-subunit rRNA gene; the amplified fragments were sequenced, edited, and compared with those of the corresponding published gene sequences. New D2-D3 and rRNA-ITS gene sequences were deposited in the GenBank database under the accession numbers KR818910 and KR818911, respectively. Based on the morphological and molecular data, the species of the cyst-forming nematode was identified as H. koreana (Vovlas et al., 1992; Mundo-Ocampo et al., 2008). The body contour of cysts was mainly subspherical, vey often with irregular shape (Fig. 1A), yellowish to light brown, thin cuticle with fine zigzag pattern, without fenestration, lacking bulla, and underbridge. Vulval lips protruded, cuticular pattern of vulval cone with a tuberculate area (Fig. 2B), and vagina embedded into vulval lips. The second-stage juveniles cylindrical and slender, hemispherical cephalic framework, with three lines in lateral field, well-developed rounded stylet knobs, tail conoid tapring to fine rounded terminus, phasmids posterior to anus. The cyst measurements were (n = 21) length 502 ± 70 (420 to 640) µm; width = 408 ± 60 (320 to 520) µm; length/width = 1.23 ± 0.09 (1.07 to 1.5) µm. The morphometric characters of vulval cone were measured (n = 7): fenestral length = 62.4 ± 6.5 (51 to 71) µm; fenestral width = 50.7 ± 3.2 (45 to 54) µm; vulval slit = 51.9 ± 4.3 (46 to 59) µm; distance from vulva to anus = 51.3 ± 4.4 (43 to 56) µm. Second-stage juveniles showed the following morphometric characters (n = 14): L = 455 ± 11.3 (437 to 472) µm; a = 29.9 ± 0.9 (28.3 to 31.5); b΄ = 2.7 ± 0.4 (2.2 to 3.5); c = 7.4 ± 0.9 (6 to 8.9); ć = 6.1 ± 0.4 (5.1 to 6.7); lip region height = 3 µm; lip region width = 7.5 ± 0.5 (7 to 8) µm; stylet length = 18.1 ± 0.5 (17 to 19) µm; anterior end to median bulb = 72.2 ± 1.7 (70 to 75) µm; anterior end to secretory-excretory pore = 99.7 ± 2.5 (96 to 103) µm; maximum body width = 15.2 ± 0.4 (15 to 16) µm; body width at anus = 10.1 ± 1 (8 to 11) µm; tail length = 62.0 ± 6.9 (51 to 74) µm; hyaline part of tail = 44.0 ± 1.8 (40 to 47) µm. The egg measurements for 11 individuals were length = 102.5 ± 7.9 (93 to 119) µm; width = 39.3 ± 4.2 (33 to 46) µm; length/width = 2.6 ± 0.3 (2.0 to 3.1). The morphology, morphometric characters and molecular data of the population of H. koreana isolated from bamboo in Iran are in agreement with those previously reported for this species (Vovlas et al., 1992; Mundo-Ocampo et al., 2008). At present, five species of Heterodera belonging to the Cyperi and Afenestrata groups were reported from bamboo, H. bamboosi (Kaushal and Swarup, 1988; Wouts and Baldwin, 1998) on Bambusa sp. from India; H. koreana on P. pubescence, P. aurea, and P. nigra from South Korea and the United States; and H. hainanensis (Zhuo et al., 2013), H. fengi (Wang et al., 2013), and H. guangdongensis (Zhuo et al., 2014) on P. pubescence from China; thus showing host suitability of bamboo for at least five species of cyst-forming nematodes. A greenhouse test performed by planting rice seed cv. Hashemi in soil containing H. koreana showed successful multiplication of Korean cyst nematode on rice seedlings after 2 mon. The exact date of the establishment of bamboo plantation in LARS is not precisely clear, but it indicates that the Korean cyst nematode was most likely brought with the imported bamboo seedlings from unknown origin several decades ago. According to our best knowledge, this is the first report of occurrence of H. koreana from Iran. So far the Korean cyst nematode was reported from South Korea, Thailand, and the United States, Florida (from nurseries); this study includes the distribution of this cyst-forming nematode in Iran and expands the information of the occurrence of H. koreana for the world.  相似文献   
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