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991.
Tzer-Min Kuo Shun-Yuan Luo Shang-Lun Chiang Chi-Pin Lee Yu-Fan Liu Jan-Gowth Chang Ming-Hsui Tsai Ying-Chin Ko 《Journal of biomedical science》2014,21(1)
Background
Arecoline, a major alkaloid in Areca nut has the ability to induce oxidative stress. The effect of Areca nut, arecoline on reducing sperm quality and quantity were documented previously using several animal models. Junction disruption by down-regulation of the junction-adhesive protein via oxidative stress is an important route mediating abnormal spermatogenesis. Therefore, in this present study, we investigated the functional role of arecoline on junctional proteins.Results
To analyze direct effects of arecoline on testis cells, confluent mouse testicular Sertoli cell line TM4 was exposed to arecoline. Arecoline decreased insoluble zonula occludens-1 (ZO-1) protein expression in TM4 cells, however, arecoline treatment increased TNF-alpha production in both TM4 and monocytic THP1 cells. In addition, ERK1/2 inhibitor PD98059 reversed arecoline effects on TNF-alpha and ZO-1.Conclusions
Arecoline increases the production of TNF-alpha and induces protein redistribution of ZO-1. All these results explain the role of arecoline in male reproductive dysfunction, besides its cytotoxic induction.Electronic supplementary material
The online version of this article (doi:10.1186/s12929-014-0093-z) contains supplementary material, which is available to authorized users. 相似文献992.
An-Shik Yang Li-Yu Tseng Chih-Chieh Chiang Wen-Yih Isaac Tseng Hsi-Yu Yu 《Computer methods in biomechanics and biomedical engineering》2014,17(5):461-473
Aortic dissection and atherosclerosis are highly fatal diseases. The development of both diseases is closely associated with highly complex haemodynamics. Thus, in predicting the onset of cardiac disease, it is desirable to obtain a detailed understanding of the flowfield characteristics in the human cardiovascular circulatory system. Accordingly, in this study, a numerical model of a normal human thoracic aorta is constructed using the geometry information obtained from a phase-contrast magnetic resonance imaging (PC-MRI) technique. The interaction between the blood flow and the vessel wall dynamics is then investigated using a coupled fluid–structure interaction (FSI) analysis. The simulations focus specifically on the flowfield characteristics and pulse wave velocity (PWV) of the blood flow. Instead of using a conventional PC-MRI method to measure PWV, we present an innovative application of using the FSI approach to numerically resolve PWV for the assessment of wall compliance in a thoracic aorta model. The estimated PWV for a normal thoracic aorta agrees well with the results obtained via PC-MRI measurement. In addition, simulations which consider the FSI effect yield a lower predicted value of the wall shear stress at certain locations in the cardiac cycle than models which assume a rigid vessel wall. Consequently, the model provides a suitable basis for the future development of more sophisticated methods capable of performing the computer-aided analysis of aortic blood flows. 相似文献
993.
L. Addis T. Chiang T. Clarke H. Hardison S. Kugler D. E. Mandelbaum E. Novotny S. Wolf L. J. Strug D. K. Pal 《Genes, Brain & Behavior》2014,13(3):333-340
Migraine headaches are a common comorbidity in Rolandic epilepsy (RE) and familial aggregation of migraine in RE families suggests a genetic basis not mediated by seizures. We performed a genome‐wide linkage analysis of the migraine phenotype in 38 families with RE to localize potential genetic contribution, with a follow‐up in an additional 21 families at linked loci. We used two‐point and multipoint LOD (logarithm of the odds) score methods for linkage, maximized over genetic models. We found evidence of linkage to migraine at chromosome 17q12‐22 [multipoint HLOD (heterogeneity LOD) 4.40, recessive, 99% penetrance], replicated in the second dataset (HLOD 2.61), and suggestive evidence at 1q23.1‐23.2, centering over the FHM2 locus (two‐point LOD 3.00 and MP HLOD 2.52). Sanger sequencing in 14 migraine‐affected individuals found no coding mutations in the FHM2 gene ATP1A2. There was no evidence of pleiotropy for migraine and either reading or speech disorder, or the electroencephalographic endophenotype of RE when the affected definition was redefined as those with migraine or the comorbid phenotype, and pedigrees were reanalyzed for linkage. In summary, we report a novel migraine susceptibility locus at 17q12‐22, and a second locus that may contribute to migraine in the general population at 1q23.1‐23.2. Comorbid migraine in RE appears genetically influenced, but we did not obtain evidence that the identified susceptibility loci are consistent with pleiotropic effects on other comorbidities in RE. Loci identified here should be fine‐mapped in individuals from RE families with migraine, and prioritized for analysis in other types of epilepsy‐associated migraine. 相似文献
994.
995.
We investigated seasonal variation of grazing impact of the pigmented nanoflagellates (PNF) with different sizes upon Synechococcus in the subtropical western Pacific coastal waters using grazing experiments with fluorescently labeled Synechococcus (FLS). For total PNF, conspicuous seasonal variations of ingestion rates on Synechococcus were found, and a functional response was observed. To further investigate the impact of different size groups, we separated
the PNF into four categories (<3, 3–5, 5–10, and >10 μm). Our results indicated that the smallest PNF (<3 μm PNF) did not
ingest FLS and was considered autotrophic. PNF of 3–5 μm in size made up most of the PNF community; however, their ingestion
on Synechococcus was too low (0.1–1.9 Syn PNF−1 h−1) to support their growth, and they had to depend on other prey or photosynthesis to survive. The ingestion rate of the 3–5 μm
group exhibited no significant seasonal variation; by contrast, the ingestion rates of 5–10 and >10 μm PNFs showed significant
seasonal variation. During the warm season, 3–5 μm PNF were responsible for the grazing of 12% of Synechococcus production, 5–10 μm PNF for 48%, and >10 μm PNF for 2%. Taken together, our results demonstrate that the PNF of 3–10 μm consumed
most Synechococcus during the warm season and exhibited a significant functional response to the increase in prey concentration. 相似文献
996.
997.
Lignans with the dibenzocyclooctadiene skeleton, kadsuphilols I-L, and one C19-homolignan, kadsuphilol M, were isolated by chromatographic fractionation of an ethyl acetate extract of the aerial parts of Kadsura philippinensis. Their structures were elucidated through extensive spectroscopic methods, including HRESIMS and 2D NMR experiments (HMQC, COSY and HMBC). The stereochemistry at the chiral centers and the biphenyl moist, were determined using NOESY, as well as analysis of CD spectra, respectively. The relative configuration of heteroclitin J was confirmed by single crystal X-ray crystallographic analysis. The in vitro radical-scavenging activities of these compounds by using DPPH were evaluated. 相似文献
998.
Enhanced levan production using chitin-binding domain fused levansucrase immobilized on chitin beads
Chung-Jen Chiang Jen-You Wang Po-Ting Chen Yun-Peng Chao 《Applied microbiology and biotechnology》2009,82(3):445-451
Levan is a homopolymer of fructose which can be produced by the transfructosylation reaction of levansucrase (EC 2.4.1.10)
from sucrose. In particular, levan synthesized by Zymomonas mobilis has found a wide and potential application in the food and pharmaceutical industry. In this study, the immobilization of
Z. mobilis levansucrae (encoded by levU) was attempted for repeated production of levan. By fusion levU with the chitin-binding domain (ChBD), the hybrid protein was overproduced in a soluble form in Escherichia coli. After direct absorption of the protein mixture from E. coli onto chitin beads, levansucrase tagged with ChBD was found to specifically attach to the affinity matrix. Subsequent analysis
indicated that the linkage between the enzyme and chitin beads was substantially stable. Furthermore, with 20% sucrose, the
production of levan was enhanced by 60% to reach 83 g/l using the immobilized levansucrase as compared to that by the free
counterpart. This production yield accounts for 41.5% conversion yield (g/g) on the basis of sucrose. After all, a total production
of levan with 480 g/l was obtained by recycling of the immobilized enzyme for seven times. It is apparent that this approach
offers a promising way for levan production by Z. mobilis levansucrase immobilized on chitin beads. 相似文献
999.
Howard H. Chiang 《Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences》2009,40(2):109-118
Historians and philosophers of science have furnished a wide array of theoretical-historiographical terms to emphasize the discontinuities among different systems of knowledge. Some of the most famous include Thomas Kuhn’s “paradigm”, Michel Foucault’s “episteme”, and the notion of “styles of reasoning” more recently developed by Ian Hacking and Arnold Davidson. This paper takes up this theoretical-historiographical thread by assessing the values and limitations of the notion of “style” for the historical and philosophical study of science. Specifically, reflecting on various methodological and theoretical concerns prompted by sexuality, translation, and East Asian studies, this paper argues that the heretofore ways in which historians and philosophers of science have used the notion of “style” are severely restricted in terms of its mere applicability to the intellectual history of Western science. The particular example of the translation of “homosexuality” into Chinese during the May Fourth era reveals that the notion of “style” has the potential of carrying a much more dynamic conceptual weight, as when used in “styles of argumentation”. The paper also engages briefly with the historiography of scientific “national styles” and ends with some concluding remarks on the limitations of “social histories from below” and the under appreciated importance of “epistemological histories of possibilities”. 相似文献
1000.
Daniel M Trindade Júlio C Silva Margareth S Navarro Iris CL Torriani Jörg Kobarg 《BMC structural biology》2009,9(1):57-12