Culture of Hypnea musciformis (Rhodophyta, Gigartinales) on artificial substrates attached to linear ropes

Hydrobiologia ◽  
1993 ◽  
Vol 260-261 (1) ◽  
pp. 415-420 ◽  
Author(s):  
Flavio A. S. Berchez ◽  
Ricardo T. L. Pereira ◽  
Neide F. Kamiya
Keyword(s):  
Artificial Substrates ◽  
Hypnea Musciformis

Production and Analysis of High Resolution Polymer Replicas of Fibrillar Collagen

1999 ◽  
Vol 5 (S2) ◽  
pp. 398-399
Author(s):  
P. Sims ◽  
B. Todd ◽  
S. Eppell ◽  
T. Li ◽  
K. Park ◽  
...  
Keyword(s):  
Cellular Response ◽  
Physical Nature ◽  
Cell Types ◽  
Artificial Substrates ◽  
Adherent Cell ◽  
Fibrillar Collagen ◽  
New Materials ◽  
Substrate Interactions ◽  
Number Of Factors ◽  
Cell Substrate

Adherent cells generally construct the immediate substrate upon which they reside. This may occur via synthesis and secretion of new materials and/or by rearrangement and modification of existing substrate. The response of adherent cell types to an existing substrate can be influenced by a number of factors which include both the chemical and physical nature of the substrate. Cell adhesion, proliferation, differentiation and death can all be substrate dependent. Much effort has been directed toward chemical modification of substrates to regulate one or more of the parameters noted above. A significant, but somewhat smaller, degree of attention has been paid to the effects of the topography and microtopography on the cell response to substrate materials. Studies to date strongly suggest the topography is a significant factor in cell-substrate interactions. As noted above, it is most probable that both the chemistry and the structure of a substrate simultaneously influence the cellular response. However we wished to determine, particularly for artificial substrates, the role which microtopography can play in cell-substrate interactions.

scholarly journals Studies on the Regulation of Algal Growth by Gibberellin

1971 ◽  
Vol 24 (4) ◽  
pp. 1115 ◽  
Author(s):  
RC Jennings
Keyword(s):  
Red Algae ◽  
Algal Growth ◽  
Red Alga ◽  
General Phenomenon ◽  
Hypnea Musciformis ◽  
Fast Growing ◽  
High Concentrations ◽  
Amo 1618 ◽  
Slow Growing

CCC and Amo.1618, at relatively high concentrations only, inhibited the growth of excised branch apices of the red alga Hypnea musciformis. Neither GA3 nor GA7 stimulated growth of the alga in the presence or absence of these compounds, and gibberellin-like material extracted from H. musciformis also failed to stimulate growth. However, both gibberellins stimulated the growth of slow-growing, but not fast-growing, branch apices of the related red alga Gracilaria verucosa. It is concluded that endogenous gibberellins may not regulate the growth of H. musciformis, but this is likely to be a peculiarity of this species and not a general phenomenon in red algae.

scholarly journals Colonization by benthic macroinvertebrates in two artificial substrate types of a Riparian Forest

2016 ◽  
Vol 28 (0) ◽  
Author(s):  
Lívia Borges dos Santos ◽  
Cyntia Goulart Côrrea Bruno ◽  
Jean Carlos Santos
Keyword(s):  
Benthic Macroinvertebrates ◽  
Benthic Community ◽  
Riparian Forest ◽  
Organic Substrate ◽  
Ecological Succession ◽  
Artificial Substrates ◽  
Significant Difference ◽  
Inorganic Substrates ◽  
Dry Seasons ◽  
Inorganic Substrate

Abstract: Aim To analyze the efficiency of organic and inorganic substrates in samples of benthic macroinvertebrates of riparian forests from the Cerrado. Specific objectives (i) characterize the ecological succession and taxonomic richness of benthic macroinvertebrates in stream affluent of a riparian forest; (ii) analyze the influence of seasonality on the colonization of macroinvertebrates; and (iii) determine the effect of the types of artificial substrates on the richness, composition and abundance of the benthic community. Methods Sampling was carried out in the rainy and dry seasons, and we installed in the watercourse two types of substrates: organic (leaf packs) and inorganic (bricks), organized in pairs. Six samples per season were done to verify colonization, succession, richness and abundance of benthic community. The substrates were carefully sorted and the organisms were identified to the lowest possible taxonomic level. Results The ecological succession was clearly observed, with the initial occurrence of Chironomidae and Baetidae (considered early colonizers), and a late occurrence of organisms such as Helotrephidae and Trichoptera (considered late colonizers). No significant difference was found in the richness and abundance among the studied seasons (rainy and dry), but the organic substrate was significantly higher than the inorganic substrate for these parameters. Conclusion Organic artificial substrates are more efficient in characterizing the community of benthic macroinvertebrates in the study area, because they are more similar to the conditions of the substrate found naturally in the environment.

scholarly journals Constitutive Expression of AID Leads to Tumorigenesis

2003 ◽  
Vol 197 (9) ◽  
pp. 1173-1181 ◽  
Author(s):  
Il-mi Okazaki ◽  
Hiroshi Hiai ◽  
Naoki Kakazu ◽  
Shuichi Yamada ◽  
Masamichi Muramatsu ◽  
...  
Keyword(s):  
T Cell ◽  
B Cells ◽  
Genome Stability ◽  
Somatic Hypermutation ◽  
Cytidine Deaminase ◽  
Point Mutations ◽  
Constitutive Expression ◽  
Cell Receptor ◽  
Genetic Alterations ◽  
Artificial Substrates

Genome stability is regulated by the balance between efficiencies of the repair machinery and genetic alterations such as mutations and chromosomal rearrangements. It has been postulated that deregulation of class switch recombination (CSR) and somatic hypermutation (SHM), which modify the immunoglobulin (Ig) genes in activated B cells, may be responsible for aberrant chromosomal translocations and mutations of non-Ig genes that lead to lymphocyte malignancy. However, the molecular basis for these genetic instabilities is not clearly understood. Activation-induced cytidine deaminase (AID) is shown to be essential and sufficient to induce both CSR and SHM in artificial substrates in fibroblasts as well as B cells. Here we show that constitutive and ubiquitous expression of AID in transgenic mice caused both T cell lymphomas and dysgenetic lesions of epithelium of respiratory bronchioles (micro-adenomas) in all individual mice. Point mutations, but not translocations, were massively introduced in expressed T cell receptor (TCR) and c-myc genes in T lymphoma cells. The results indicate that AID can mutate non-Ig genes including oncogenes, implying that aberrant AID expression could be a cause of human malignancy.

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