scholarly journals Species-specific chemical compositions of defense secretions from Parafontaria tonominea Attems and Riukiaria semicircularis semicircularis Takakuwa(Polydesmida: Xystodesmidae).

2002 ◽  
Vol 37 (1) ◽  
pp. 73-78 ◽  
Author(s):  
Hisashi Ômura ◽  
Yasumasa Kuwahara ◽  
Tsutomu Tanabe
Keyword(s):  
Chemical Compositions ◽  
Specific Chemical ◽  
Defense Secretions ◽  
Species Specific

scholarly journals Blooms of Toxic Cyanobacterium Nodularia spumigena in Norwegian Fjords During Holocene Warm Periods

Toxins ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 257
Author(s):  
Robert Konkel ◽  
Anna Toruńska-Sitarz ◽  
Marta Cegłowska ◽  
Žilvinas Ežerinskis ◽  
Justina Šapolaitė ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Phytoplankton Community ◽  
Sediment Cores ◽  
Specific Chemical ◽  
Nodularia Spumigena ◽  
History Of ◽  
Recent Sediments ◽  
Species Specific ◽  
Ecosystem Changes ◽  
Deep Sediments

In paleoecological studies, molecular markers are being used increasingly often to reconstruct community structures, environmental conditions and ecosystem changes. In this work, nodularin, anabaenopeptins and selected DNA sequences were applied as Nodularia spumigena markers to reconstruct the history of the cyanobacterium in the Norwegian fjords. For the purpose of this study, three sediment cores collected in Oslofjorden, Trondheimsfjorden and Balsfjorden were analyzed. The lack of nodularin in most recent sediments is consistent with the fact that only one report on the sporadic occurrence and low amounts of the cyanobacterium in Norwegian Fjords in 1976 has been published. However, analyses of species-specific chemical markers in deep sediments showed that thousands of years ago, N. spumigena constituted an important component of the phytoplankton community. The content of the markers in the cores indicated that the biomass of the cyanobacterium increased during the warmer Holocene periods. The analyses of genetic markers were less conclusive; they showed the occurrence of microcystin/nodularin producing cyanobacteria of Nostocales order, but they did not allow for the identification of the organisms at a species level.

Species-Specific Chemical Signatures in Scale Insect Honeydew

2011 ◽  
Vol 37 (11) ◽  
pp. 1231-1241 ◽  
Author(s):  
Manpreet K. Dhami ◽  
Robin Gardner-Gee ◽  
Jeremy Van Houtte ◽  
Silas G. Villas-Bôas ◽  
Jacqueline R. Beggs
Keyword(s):  
Scale Insect ◽  
Specific Chemical ◽  
Chemical Signatures ◽  
Species Specific

Abstract 121: Combinatorial Tailored Polymers Enhanced Maturation of Human iPSC-CMs

2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Young Wook Chun ◽  
Tromondae K Feaster ◽  
Timothy Boire ◽  
Calvin C Sheng ◽  
Hak-Joon Sung ◽  
...  
Keyword(s):  
Mitochondrial Function ◽  
Human Heart ◽  
In Vitro Maturation ◽  
Heart Diseases ◽  
Stem Cell Differentiation ◽  
Polymer Composition ◽  
Chemical Compositions ◽  
Specific Chemical ◽  
Human Cardiomyocytes

There is a tremendous interest in human cardiomyocytes generated from patient-derived induced pluripotent stem cells (iPSC-CMs) for the study and possible treatment of human heart diseases. Despite their vast potential, a significant impediment to a broader application of iPSC-CMs to study human myocyte biology is the structural and functional immaturity of iPSC-CMs. Growing evidence indicates that synthetic polymers utilized as extracellular substrates can exert significant effects on in vitro tissue generation, although the underlying mechanisms remain largely unknown. Based on the profound impact of the extracellular matrix of developing embryos on in vivo organogenesis, we hypothesize that engineered polymer substrates will likewise influence in vitro maturation of iPSC-CMs. A subset of combinatorial polymers was synthesized by polymerizing poly(ε-caprolacton) (PCL), polyethylene glycol (PEG), and carboxylated PCL (cPCL), abbreviated as x%PEG-y%PCL-z%cPCL (x, y, and z: molar %). We investigated effects of the polymer composition on maturation of iPSC-CMs with respect to the beating behavior, mitochondrial function and molecular profiles after 30 days in culture on polymer scaffolds. Results showed the 4%PEG-96%PCL scaffold promoted the most active beating in iPSC-CMs at 30 days and further, that the mitochondrial function, as assessed by tetramethyl rhodamine methylester (TMRM) was significantly increased in the iPSC-CMs cultured on 4%PEG-96%PCL over other polymers. Molecular profiling analysis indicates 4%PEG-96%PCL scaffolds enhanced the expression of MYL2 (a commonly accepted marker of mature ventricular myocytes) as well as of components of the intermediate filaments linking the plasma membrane to the myofilament. In summary, although the polymers we used here exhibit similar physicochemical properties, they have divergent effects on iPSC-CM differentiation. Thus, specific chemical compositions of synthetic substrates can exert profound influence on in vitro maturation of hiPSC-CMs. Our work exploring the effects of synthetic biomaterials on human stem cell differentiation could pave the way for a successful translation of ongoing advances in tissue engineering to new treatments for human heart diseases.

Urine-Derived Compound Evokes Membrane Responses in Mouse Vomeronasal Receptor Neurons

1997 ◽  
Vol 77 (5) ◽  
pp. 2856-2862 ◽  
Author(s):  
Robert L. Moss ◽  
Robert E. Flynn ◽  
Xin-Ming Shen ◽  
Carol Dudley ◽  
Jiming Shi ◽  
...  
Keyword(s):  
Outward Current ◽  
Membrane Conductance ◽  
Reproductive Function ◽  
Vomeronasal Organ ◽  
Intact Male ◽  
Specific Chemical ◽  
Membrane Hyperpolarization ◽  
Vomeronasal Receptor ◽  
Receptor Neurons ◽  
Species Specific

Moss, Robert L., Robert E. Flynn, Xin-Ming Shen, Carol Dudley, Jiming Shi, and Milos Novotny. Urine-derived compound evokes membrane responses in mouse vomeronasal receptor neurons. J. Neurophysiol. 77: 2856–2862, 1997. Sensory neurons of the vomeronasal organ (VNO) are thought to detect species-specific chemical signals important for reproductive function. The electrical properties of VNO neurons have begun to be characterized in a variety of species; however, the response of VNO neurons to possible physiological ligands has not yet been reported. One physiological effector, dehydro-exo-brevicomin (DHB), is found in the urine of intact male mice and affects the estrous cycle of female mice. In the present study, dissociated VNO neurons were voltage- or current-clamped and their response to DHB was determined. Approximately 26% of VNO neurons responded to DHB with an outward current at negative holding potentials; the current reversed at approximately +4 mV. Application of DHB in current-clamp mode produced membrane hyperpolarization and/or a reduction in the firing of action potentials. Because membrane conductance was shown to be decreased during application of DHB, the results suggest that the outward current associated with DHB application is a reflection of a reduction in inward current caused by closing an ion channel. This study provides the first evidence that a compound found in male urine directly affects VNO neurons.

Suberized Cell Walls of Cork from Cork Oak Differ from Other Species

2010 ◽  
Vol 16 (5) ◽  
pp. 569-575 ◽  
Author(s):  
Rita Teresa Teixeira ◽  
Helena Pereira
Keyword(s):  
Secondary Wall ◽  
Three Dimensional ◽  
Spatial Location ◽  
Typical Feature ◽  
Quercus Suber ◽  
Uranyl Acetate ◽  
Calotropis Procera ◽  
Specific Chemical ◽  
Transmission Electron ◽  
Species Specific

AbstractPlants have suberized cells that act as protective interfaces with the environment or between different plant tissues. A lamellar structure of alternating dark and light bands has been found upon transmission electron microscopy (TEM) observation of cork cells and considered a typical feature of the suberized secondary wall. We observed cork cells from periderms of Quercus suber, Quercus cerris, Solanum tuberosum, and Calotropis procera by TEM after uranyl acetate and lead citrate staining. A lamellated structure was observed in S. tuberosum and C. procera but not in Q. suber and Q. cerris where the suberized cell wall showed a predominantly hyaline aspect with only a dark dotted staining. Removal of suberin from Q. suber cells left a thinner secondary wall that lost the translucent aspect. We hypothesize that the species' specific chemical composition of suberin will result in different three-dimensional macromolecular development and in a different spatial location of lignin and other aromatics. A lamellated ultrastructure is therefore not a general feature of suberized cells.

scholarly journals Multivariate Analysis of Seed Chemical Diversity among Jatropha curcas in Botswana

Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1570
Author(s):  
Shota Tadano ◽  
Gwafila Chiyapo ◽  
Yudai Ishimoto ◽  
Takafumi Konaka ◽  
Charles Mazereku ◽  
...  
Keyword(s):  
Jatropha Curcas ◽  
Seed Weight ◽  
Phorbol Esters ◽  
Chemical Properties ◽  
Principal Component ◽  
Chemical Diversity ◽  
Chemical Compositions ◽  
Severe Drought ◽  
Bioenergy Feedstock ◽  
Specific Chemical

Jatropha (Jatropha curcas L.) has been identified as a potential bioenergy feedstock in arid regions, but knowledge of the diversity of its chemical characteristics is limited. In this study, 61 Jatropha accessions growing in Botswana, where both severe drought and winter frosts frequently occur, were analyzed for their seed chemical properties. Histogram analyses and meta-analysis comparisons with seeds from other countries/continents showed that the median/mean dry seed weight, toxic compound phorbol esters, and C18:0 fatty acid levels in the Botswanan accessions were lower than those from other countries/continents. A clustered heat map analysis indicated five clades for the Botswanan accessions, and their physicochemical traits were also categorized into five groups. Many positive and negative correlations were observed among the chemical traits, including negative correlations between the C18:3 (linolenic acid) content and yield-related traits (lipid content and dry seed weight). Principal component analysis highlighted the existence of accessions with highly deviated seed chemical compositions, such as those enriched in C18:0/C18:1 and C16:0/C16:1/C18:3 fatty acids. Overall, the present study suggests considerable diversity in the seed chemical compositions of Botswanan Jatropha accessions. Various accessions could be useful as feedstock for specific industrial products, as well as for breeding materials for the fortification of specific chemical ingredients.

scholarly journals Exploiting intraspecific competitive mechanisms to control invasive cane toads ( Rhinella marina )

2012 ◽  
Vol 279 (1742) ◽  
pp. 3436-3442 ◽  
Author(s):  
Michael R. Crossland ◽  
Takashi Haramura ◽  
Angela A. Salim ◽  
Robert J. Capon ◽  
Richard Shine
Keyword(s):  
Invasive Species ◽  
Communication Systems ◽  
Native Species ◽  
Negative Effects ◽  
Specific Chemical ◽  
Rhinella Marina ◽  
Invasive Species Control ◽  
Tropical Australia ◽  
Competitive Mechanisms ◽  
Species Specific

If invasive species use chemical weapons to suppress the viability of conspecifics, we may be able to exploit those species-specific chemical cues for selective control of the invader. Cane toads ( Rhinella marina ) are spreading through tropical Australia, with negative effects on native species. The tadpoles of cane toads eliminate intraspecific competitors by locating and consuming newly laid eggs. Our laboratory trials show that tadpoles find those eggs by searching for the powerful bufadienolide toxins (especially, bufogenins) that toads use to deter predators. Using those toxins as bait, funnel-traps placed in natural waterbodies achieved near-complete eradication of cane toad tadpoles with minimal collateral damage (because most native (non-target) species are repelled by the toads' toxins). More generally, communication systems that have evolved for intraspecific conflict provide novel opportunities for invasive-species control.

Female choice for large body size in the cave molly, Poecilia mexicana (Poeciliidae, Teleostei): influence of species- and sex-specific cues

Behaviour ◽  
2007 ◽  
Vol 144 (10) ◽  
pp. 1147-1160 ◽  
Author(s):  
Jakob Parzefall ◽  
Rüdiger Riesch ◽  
Ingo Schlupp ◽  
Martin Plath
Keyword(s):  
Body Size ◽  
Visual Cues ◽  
Chemical Cues ◽  
Large Body ◽  
Large Body Size ◽  
Specific Chemical ◽  
Stimulus Fish ◽  
Poecilia Mexicana ◽  
Species Specific ◽  
Cave Molly

AbstractPrevious studies revealed that females of a cave form of the livebearing fish Poecilia mexicana (cave molly) have maintained the ancestral visual preference for large males, but — as an adaptation to life in darkness — they have evolved the novel capability to assess male size non-visually. Here we examined the mechanisms by which non-visual mate choice for large body size occurs. Are sex- and species-specific chemical cues involved in this preference for large conspecifics? We gave focal females an opportunity to associate with a large and a small stimulus fish in simultaneous choice tests, whereby the females could perceive either multiple cues (visual plus non-visual) from the stimulus fish, solely non-visual cues in darkness, or solely visual cues. Stimulus fish were two conspecific males, conspecific females, or heterospecific females (Xiphophorus hellerii). Cave molly females showed a significant preference for large conspecific males and for large conspecific females in all treatments. When a large and a small swordtail female were presented, cave molly females showed a preference for the larger fish only when exclusively visual cues from the stimulus fish were available. The non-visual preference for large body size appears to be mediated by species- but not by sex-specific cues, suggesting that species-specific chemical cues play an important role during mate choice.

Sign in / Sign up

Export Citation Format

Share Document