170 research outputs found
Tenascin-C and mechanotransduction in the development and diseases of cardiovascular system
Living tissue is composed of cells and extracellular matrix (ECM). In the heart and blood vessels, which are constantly subjected to mechanical stress, ECM molecules form well-developed fibrous frameworks to maintain tissue structure. ECM is also important for biological signaling, which influences various cellular functions in embryonic development, and physiological/pathological responses to extrinsic stimuli. Among ECM molecules, increased attention has been focused on matricellular proteins. Matricellular proteins are a growing group of non-structural ECM proteins highly up-regulated at active tissue remodeling, serving as biological mediators. Tenascin-C (TNC) is a typical matricellular protein, which is highly expressed during embryonic development, wound healing, inflammation, and cancer invasion. The expression is tightly regulated, dependent on the microenvironment, including various growth factors, cytokines, and mechanical stress. In the heart, TNC appears in a spatiotemporal-restricted manner during early stages of development, sparsely detected in normal adults, but transiently re-expressed at restricted sites associated with tissue injury and inflammation. Similarly, in the vascular system, TNC is strongly up-regulated during embryonic development and under pathological conditions with an increase in hemodynamic stress. Despite its intriguing expression pattern, cardiovascular system develops normally in TNC knockout mice. However, deletion of TNC causes acute aortic dissection (AAD) under strong mechanical and humoral stress. Accumulating reports suggest that TNC may modulate the inflammatory response and contribute to elasticity of the tissue, so that it may protect cardiovascular tissue from destructive stress responses. TNC may be a key molecule to control cellular activity during development, adaptation, or pathological tissue remodeling
Phylogeographical patterns of a generalist acorn weevil: insight into the biogeographical history of broadleaved deciduous and evergreen forests
<p>Abstract</p> <p>Background</p> <p>Climatic changes during glacial periods have had a major influence on the recent evolutionary history of living organisms, even in temperate forests on islands, where the land was not covered with ice sheets. We investigated the phylogeographical patterns of the weevil <it>Curculio sikkimensis </it>(Curculionidae), a generalist seed predator of Fagaceae plants living in both deciduous oak and evergreen forests of Japan. Its genetic structure was compared to that of another host-specific seed predator, <it>C. hilgendorfi</it>, inhabiting only evergreen forests.</p> <p>Results</p> <p>We examined 921 bp of mitochondrial DNA for 115 individuals collected from 33 populations of <it>C. sikkimensis </it>from 11 plant species of three genera, <it>Quercus</it>, <it>Lithocarpus</it>, and <it>Castanopsis</it>. An analysis of molecular variance revealed that a large proportion (almost 50%, <it>P </it>< 0.001) of the total genetic variance could be explained by differences between two geographical regions, the southwestern and northeastern parts of the main islands of Japan. In contrast, no significant genetic differentiation of the weevil was observed among vegetation types of their utilized host plant species. The phylogeographical patterns of the generalist and the host-specific seed predator exhibited a congruent genetic boundary in the Chugoku-Shikoku region.</p> <p>Conclusion</p> <p>Our results suggest that geology and historical environment have contributed to shaping the present genetic structure of <it>C. sikkimensis</it>. The geographical patterns of genetic differentiation in the Chugoku-Shikoku region observed in the two types of Fagaceae-associated <it>Curculio </it>in this study have also been observed in several plant species growing in warm and cool temperate zones of Japan. The occurrence of this common pattern suggests that deciduous oak and evergreen forests of Japan survived together, or adjacent to each other, in small refugia during glacial ages, in the southwestern and northeastern parts of the main islands, although these two types of forests are presently distributed in cool and warm temperate zones of Japan, respectively.</p
Syntheses of (±)-4-amino-1,3,4,5-tetrahydrobenz[cd]indole-4-carboxylic acid, (±)-4-N,N-dipropylamino-4-hydroxymethyl- and (±)-4-propyloxy-1,3,4,5-tetrahydrobenz[cd]indole
金沢大学大学院自然科学研究科生理活性物質科学金沢大学薬学
Antioxidant Activity of β-Glucan
β-Glucans extracted from barley, which mainly contains β-(1,3-1,4)-D-glucan, are used extensively as supplements and food additives due to their wide biologic activities, including a reduction in blood lipid level. In this study, the antioxidant activity of β-glucan was examined to assess potential new benefits associated with β-glucan, because oxidative stress is considered one of the primary causal factors for various diseases and aging. β-Glucan extracted from barley was found to possess significant antioxidant activity. The amount of antioxidant activity was influenced by different physiologic properties (e.g., structure and molecular size) of β-glucan, which varied depending on the source and extraction method used. The antioxidant activity of β-glucan was significantly higher than that of various polymers that are used as food additives. These results indicate that β-glucan has promise as a polymeric excipient for supplement and food additive with antioxidant and other benefits, which may contribute to enhancing health and beauty
Simple of syntheses of marine alkaloid, (±)-helonin A, and its analogs
金沢大学大学院自然科学研究科生理活性物質科学金沢大学薬学
A simple four step synthesis and optical resolution of 4-nitro-1,3,4,5-tetrahydrobenz[cd]indole, and the synthesis of 1-hydroxy derivatives of 4-nitro- and 4-amino-1,3,4,5-tetrahydrobenz[cd]indole
金沢大学大学院自然科学研究科生理活性物質科学金沢大学薬学
Syntheses of 4-amino-, 4-hydroxy-, and 4-nitro-1,3,4,5-tetrahydrobenz[cd]indoles and its bromination
Simple synthetic method for 4-nitro-1,3,4,5-tetrahydrobenz[cd]indole (6) is established from indole-3-carboxaldehyde (7). With 6 in hand, various derivatives of 4-amino-, 4-hydroxy- and 4-amino-4-hydroxymethyl-1,3,4,5-tetrahydrobenz[cd]indoles become readily available. Bromination of 6 afforded useful building blocks for further manipulation. Successful optical resolution of 6 by chiral column chromatography is also reported. © 2014 The Japan Institute of Heterocyclic Chemistry
MicroRNA in Cervical Cancer: OncomiRs and Tumor Suppressor miRs in Diagnosis and Treatment
Cervical cancer is a female-specific disease with a high incidence and mortality. MicroRNAs (miRNAs) are implicated in posttranscriptional regulation of gene expression and in the pathogenic mechanisms of cancer, suggesting their importance in diagnosis and treatment. miRNAs may have roles in the pathogenesis of cervical cancer based on the increases or decreases in several specific miRNAs found in patients with this disease. The miRNAs implicated in cervical cancer are miR-21, miR-126, and miR-143, and clinical application of these miRNAs for diagnosis and treatment is under investigation. Methods for diagnosis of cervical cancer include analysis of changes in the levels of specific miRNAs in serum and determination of aberrant hypermethylation of miRNAs. Supplementation of miR-143 or inhibition of miR-21 activity in vivo may be therapeutic strategy for cervical cancer. Previous approaches to development of siRNA as a drug have provided information for establishment of therapy based on these approaches, and an anti-miR-21 inhibitor has been developed. miRNAs also have effects on drug resistance and may be useful in combination therapy with other drugs
Sleeping arrangement and house structure affect bed net use in villages along Lake Victoria
<p>Abstract</p> <p>Background</p> <p>Although insecticide-treated bed nets are effective tools, use often does not follow ownership. House structure and space arrangements may make the attempt to use bed nets difficult, especially for school age children. The objectives of this study were to explore whether an individual's sleeping arrangements and house structure affect bed net use in villages along Lake Victoria in western Kenya.</p> <p>Methods</p> <p>Sleeping arrangements of residents were directly observed for use of a bed net, use of a bed, and location. House size, number and types of rooms, bed availability, and residents' ages were estimated. The family heads and mothers were asked about the reason for not using bed nets. Individual bed net use was examined against age and sleeping arrangement. Net use at the household level was examined against four variables: bed availability, bed net availability, house size, and number of rooms.</p> <p>Results</p> <p>Bed net use by children between five and 15 years of age was lower than that among the other age classes. However, age was dropped from the final model, and sleeping arrangement was significantly associated with net use. Net use was significantly associated with bed availability, number of rooms and their interaction.</p> <p>Conclusion</p> <p>Net use was affected by sleeping arrangement and availability of suitable locations for hanging nets, in addition to net availability. Most residents had likely not realized that sleeping arrangement was a factor in net use. The ease of hanging a net is particularly important for children.</p
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